Shock-absorbing mechanism for movable mirror of camera

ABSTRACT

A movable mirror shock-absorbing mechanism of a camera is provided and includes a movable mirror rotatable between a viewfinder light-guiding position and a retracted position, a first shock-absorbing member which comes into contact with, and is pressed and moved by, the movable mirror to absorb shock of the movable mirror when the movable mirror rotates between the viewfinder light-guiding position and the retracted position, and a second shock-absorbing member to absorb shock of the movable mirror when the movable mirror rotates in the opposite.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a divisional of pending U.S. patent application Ser.No. 13/231,095, filed on Sep. 13, 2011, which claims priority toJapanese Application No. 2011-190289, filed Sep. 1, 2011, and No.2010-206045, filed Sep. 14, 2010, and No. 2010-206046, filed Sep. 14,2010 and No. 2010-206047, filed Sep. 14, 2010, the contents of which areexpressly incorporated herein by reference in their entireties.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a drive mechanism for driving a movablemirror provided in a camera, and in particular to a shock-absorbingmechanism, provided in association with the drive mechanism, for themovable mirror.

2. Description of the Related Art

In SLR cameras, a movable mirror (quick-return mirror) is installed tobe capable of moving up and down, more specifically, capable of rotatingbetween a viewfinder light-guiding position (mirror-down position), inwhich the movable mirror is positioned onto a photographing optical pathto reflect incident light from an object (object-emanated light) towarda viewfinder optical system, and a retracted position (mirror-upposition), in which the movable mirror is retracted from thephotographing optical path to allow the object-emanated light to traveltoward the shutter. Rotation (swinging) of the movable mirror is limitedby engagement of the movable mirror with a positioning member(s)provided in a mirror box which accommodates the movable mirror; however,if the rotating speed of the movable mirror is fast, the movable mirrorbounces (vibrates) due to shock caused upon coming into contact with thepositioning member(s). This bouncing of the movable mirror makes theimage that is viewed through the viewfinder unstable, causing an adverseeffect on the viewing performance of the viewfinder. Additionally, in acamera which is structured to lead light from an object to a distancemeasuring sensor and a photometering sensor via a movable mirror, aprecise distance measuring operation or photometering operation cannotbe performed during such bouncing of the movable mirror, which restrictssequential photographing performance. Because of such reasons, variousshock-absorbing mechanisms which absorb shock of the movable mirror whenit rotates to reduce bouncing of the movable mirror have been proposed.Examples of conventional shock-absorbing mechanisms include a type ofshock-absorbing mechanism which makes the movable mirror come intocontact with an elastic member and another type of shock-absorbingmechanism which makes the movable mirror come into contact with amovable member which is biased tending to move by a biasing member.

A high positioning accuracy of the movable mirror is requiredspecifically when the movable mirror is in the aforementioned viewfinderlight-guiding position, in which the movable mirror exerts a directinfluence on the viewing performance of the viewfinder, and when themovable mirror is in the aforementioned retracted position, in which anexposure operation is performed; accordingly, it is necessary for thepositioning of the movable mirror to be made using a special positioningmember and for the shock-absorbing mechanism to be constructed so as notto interfere with the positioning that is made using this specialpositioning member. In other words, a shock-absorbing mechanism for amovable mirror provided in a camera is required not only to reducebouncing of the movable mirror when rotating, but also is required notto interfere with the positioning of the movable mirror upon reachingeither rotational limit thereof; however, satisfying these requirementstends to complicate the structure of the shock-absorbing mechanism.

Furthermore, if the biasing force that acts on a shock-absorbing movablemember(s) (shock-absorbing member) is strengthened, the absorbingefficiency of the moving energy of the movable mirror increases;however, if the biasing force becomes too strong, the load on themovable mirror becomes excessive, so that there is a risk of not beingable to reliably move the shock-absorbing movable member to a positioncorresponding to a mirror-up position or a mirror-down position of themovable mirror. On the other hand, if the biasing force that acts on theshock-absorbing movable member is too weak, a sufficient shock-absorbingcapability cannot be obtained. Hence, there is a need for ashock-absorbing mechanism which can reliably operate a movable mirrorwhile having a high shock-absorbing capability. In an attempt to solvethe above-described problem, it is conceivable to provide an independentdrive mechanism that moves the shock-absorbing movable member to apredetermined position at the final stage of the mirror-upoperation/mirror-down operation; however, the number of componentsincreases and the structure therefor becomes complicated, having thedisadvantage of increasing (manufacturing) costs and increasing the sizeof the camera itself.

SUMMARY OF THE INVENTION

The present invention provides a shock-absorbing mechanism for a movablemirror of a camera which absorbs shock of the movable mirror when itoperates and which makes an accurate positioning of the movable mirrorpossible upon the movable mirror reaching either rotational limitthereof even though the shock-absorbing mechanism is small in the numberof components and simple in structure.

In addition, a shock-absorbing mechanism for a movable mirror of acamera has been required to display a high shock-absorbing capabilitywith as simple and compact structure as possible, and the presentinvention provides a shock-absorbing mechanism for a movable mirror of acamera which is simple and compact in structure, and superior inshock-absorbing capability when the movable mirror rotates.

In addition, the present invention provides a movable mirrorshock-absorbing mechanism which can achieve both a high shock-absorbingcapability and a reliable driving operation of the movable mirror, whilehaving a simple and compact structure.

According to an aspect of the present invention, a movable mirrorshock-absorbing mechanism of a camera is provided, including a movablemirror which is supported to be rotatable between a viewfinderlight-guiding position, in which the movable mirror is positioned in aphotographing optical path to reflect incident light from an objecttoward a viewfinder optical system, and a retracted position, in whichthe movable mirror is retracted from the photographing optical path toallow the object light to travel toward a photographic light-receivingmedium; a mirror-advancing shock-absorbing member which comes intocontact with, and is pressed and moved by, the movable mirror to absorbshock of the movable mirror when the movable mirror rotates from theretracted position to the viewfinder light-guiding position; and amirror-retracting shock-absorbing member which comes into contact with,and is pressed and moved by, the movable mirror to absorb shock of themovable mirror when the movable mirror rotates from the viewfinderlight-guiding position to the retracted position. The mirror-advancingshock-absorbing member is held in a position so as not to contact withthe movable mirror by the mirror-retracting shock-absorbing member whenthe movable mirror is in the viewfinder light-guiding position.

According to this structure, the mirror-advancing shock-absorbingmember, which absorbs shock of the movable mirror when the movablemirror rotates to the viewfinder light-guiding position, is held in aposition (non-contact position) so as not to be contact with the movablemirror in a state where the movable mirror has reached the viewfinderlight-guiding position, and accordingly, the viewfinder light-guidingposition of the movable mirror can be set with high precision withoutbeing affected by the mirror-advancing shock-absorbing member. Inaddition, since the mirror-retracting shock-absorbing member, whichabsorbs shock of the movable mirror when the movable mirror rotates tothe retracted position, is also used as a holder which holds themirror-advancing shock-absorbing member in the aforementionednon-contact position, the movable mirror shock-absorbing mechanism has asmall number of components and is simple in structure, which makes itpossible to achieve miniaturization of the camera and a reduction of theproduction cost.

It is desirable for the movable mirror shock-absorbing mechanism toinclude a first biaser which biases the mirror-advancing shock-absorbingmember in a direction to bring the mirror-advancing shock-absorbingmember into contact with the movable mirror; and a second biaser whichbiases the mirror-retracting shock-absorbing member in a direction tobring the mirror-retracting shock-absorbing member into contact with themovable mirror. The mirror-advancing shock-absorbing member is rotatableabout a shaft that is substantially parallel to an axis of rotation ofthe movable mirror. The movable mirror presses the mirror-advancingshock-absorbing member against a biasing force of the first biaser whenrotating from the retracted position to the viewfinder light-guidingposition. The mirror-retracting shock-absorbing member is linearlymovable along a plane substantially orthogonal to the axis of rotationof the movable mirror. The mirror-retracting shock-absorbing memberincludes a rotation-restricting portion which moves into a path ofrotational movement of the mirror-advancing shock-absorbing member torestrict a range of rotational movement of the mirror-advancingshock-absorbing member when the mirror-retracting shock-absorbing membermoves to a movement limit thereof in a biasing direction of the secondbiaser, and which retracts from the path of rotational movement of themirror-advancing shock-absorbing member when the mirror-retractingshock-absorbing member is pressed and moved by the movable mirror in adirection opposite to the biasing direction of the second biaser.

It is desirable for the mirror-advancing shock-absorbing member toinclude a rotationally restricted surface which comes into contact withthe rotation-restricting portion of the mirror-retractingshock-absorbing member when movement of the mirror-advancingshock-absorbing member is restricted by the mirror-retractingshock-absorbing member; and a rotation allowance surface which ispositioned radially outside of the rotationally restricted surface, withrespect to the shaft, and allows the mirror-advancing shock-absorbingmember to rotate while restricting movement of the mirror-retractingshock-absorbing member in the biasing direction of the second biaserwhen in contact with the rotation-restricting portion of themirror-retracting shock-absorbing member.

It is desirable for the camera to include a mirror box whichaccommodates and supports the movable mirror between a pair oflaterally-opposed side walls, wherein the mirror-advancingshock-absorbing member and the mirror-retracting shock-absorbing memberare supported by one of the pair of side walls of the mirror box. Themirror-advancing shock-absorbing member and the mirror-retractingshock-absorbing member include a protruded contact portion and aprotruded contact portion, respectively, each of which projects into themirror box to be contactable with the movable mirror. The mirror boxincludes a mirror positioning portion which projects from the other ofthe pair of side walls to define the viewfinder light-guiding positionof the movable mirror. The mirror-advancing shock-absorbing member comesinto contact with the rotation-restricting portion of themirror-retracting shock-absorbing member to be held in a position tomake the protruded contact portion of the mirror-retractingshock-absorbing member disengaged from the movable mirror when themovable mirror comes into contact with the mirror positioning portion tobe held in the in the viewfinder light-guiding position.

It is desirable for the mirror box to include a first limit portionwhich defines a rotational limit of the mirror-advancing shock-absorbingmember in a biasing direction of the first biaser, and a second limitportion which defines a movement limit of the mirror-retractingshock-absorbing member in the biasing direction of the second biaser.

It is desirable for the first biaser to include a torsion spring whichis engaged with the mirror box and the mirror-advancing shock-absorbingmember, and for the second biaser to include an extension spring whichis engaged with the mirror box and the mirror-retracting shock-absorbingmember.

It is desirable for the first biaser to include a torsion spring whichis engaged with the mirror box and the mirror-advancing shock-absorbingmember, and for the second biaser to include a torsion spring which isengaged with the mirror box and the mirror-retracting shock-absorbingmember.

In an embodiment, a movable mirror shock-absorbing mechanism of a camerais provided, including a movable mirror which is supported to be movablebetween a viewfinder light-guiding position, in which the movable mirroris positioned in a photographing optical path to reflect incident lightfrom an object toward a viewfinder optical system, and a retractedposition, in which the movable mirror is retracted from thephotographing optical path to allow the object light to travel toward aphotographic light-receiving medium; a first shock-absorbing memberwhich comes into contact with, and is pressed and moved by, the movablemirror to absorb shock of the movable mirror when the movable mirrorrotates in one direction between the retracted position and theviewfinder light-guiding position; a second shock-absorbing member whichcomes into contact with, and is pressed and moved by, the movable mirrorto absorb shock of the movable mirror when the movable mirror rotates inthe other direction between the viewfinder light-guiding position andthe retracted position; and an engaging mechanism provided on the firstshock-absorbing member and the second shock-absorbing member. A range ofmovement of at least one of the first shock-absorbing member and thesecond shock-absorbing member includes a shock-absorbing moving range,in which the at least one of the first shock-absorbing member and thesecond shock-absorbing member comes into contact with and is pressed andmoved by the movable mirror, and an overrun range that exceeds theshock-absorbing moving range in which the at least one of the firstshock-absorbing member and the second shock-absorbing member is not incontact with the movable mirror. When one of the first shock-absorbingmember and the second shock-absorbing member, the range of movement ofwhich includes the overrun range, is pressed and moved by the movablemirror, the engaging mechanism engages the one of the firstshock-absorbing member and the second shock-absorbing member with theother of the first shock-absorbing member and the second shock-absorbingmember to be held in the overrun range.

According to this structure, at least one of the two shock-absorbingmembers, which absorb shock of the movable mirror when the movablemirror rotates to the viewfinder light-guiding position and theretracted position, respectively, also serves as a holder which holdsthe mirror-up shock-absorbing lever in the overrun range, in which theother shock-absorbing member is not in contact with the movable mirror;accordingly, the positioning of the movable mirror can be made with highprecision without being affected by the shock-absorbing members.Moreover, the structure of the movable mirror shock-absorbing mechanismcan be simplified by reducing the number of components thereof.

It is desirable for a range of movement of at least the firstshock-absorbing member to include the overrun range, wherein theengaging mechanism includes a first biaser which biases the firstshock-absorbing member in a direction opposite to a pressing-movingdirection in which the first shock-absorbing member is pressed and movedby the movable mirror; a second biaser which biases the secondshock-absorbing member in a direction opposite to a pressing-movingdirection in which the second shock-absorbing member is pressed andmoved by the movable mirror; an engaging surface formed on the firstshock-absorbing member to face in a biasing direction of the firstbiaser; and a movement restricting portion which is formed on the secondshock-absorbing member and moves into a path of movement of the engagingsurface of the second shock-absorbing member in accordance with movementof the second shock-absorbing member. When the second shock-absorbingmember moves in a biasing direction of the second biaser, the movementrestricting portion moves into the path of movement of the engagingsurface of the first shock-absorbing member, and the engaging surfaceand the movement restricting portion are engaged with each other by abiasing force of the first biaser to hold the first shock-absorbingmember in the overrun range. When the second shock-absorbing member ispressed and moved by the movable mirror against a biasing force of thesecond biaser, the movement restricting portion retracts from the pathof movement of the engaging surface of the first shock-absorbing member.

In an embodiment, a movable mirror shock-absorbing mechanism of acamera, including a movable mirror which is supported to be rotatablebetween a viewfinder light-guiding position, in which the movable mirroris positioned in a photographing optical path to reflect incident lightfrom an object toward a viewfinder optical system, and a retractedposition, in which the movable mirror is retracted from thephotographing optical path to allow the object light to travel toward aphotographic light-receiving medium; a mirror-retracting shock-absorbingmember which comes into contact with, and is pressed and moved in afirst pressing-moving direction by, the movable mirror to absorb shockof the movable mirror when the movable mirror rotates from theviewfinder light-guiding position to the retracted position; and amirror-advancing shock-absorbing member which is held in a limitposition in which a range of movement of the mirror-retractingshock-absorbing member in a direction opposite to the firstpressing-moving direction is limited when the movable mirror is in theretracted position, wherein the mirror-advancing shock-absorbing membercomes into contact with, and is pressed and moved in a secondpressing-moving direction by, the movable mirror from the limit positionto release the limitation of the range of movement of themirror-retracting shock-absorbing member and to absorb shock of themovable mirror when the movable mirror rotates from the retractedposition to the viewfinder light-guiding position.

According to this structure, the bouncing action of themirror-retracting shock-absorbing member, which absorbs shock of themovable mirror when the movable mirror rotates to the retractedposition, is limited by the mirror-advancing shock-absorbing member,which absorbs shock of the movable mirror when the movable mirrorrotates to the viewfinder light-guiding position, so that no additionalmember for suppressing bouncing of the mirror-retracting shock-absorbingmember is required. Accordingly, the movable mirror shock-absorbingmechanism has a small number of components and is simple in structure,which makes it possible to achieve miniaturization of the camera and areduction of the production cost.

It is desirable for the movable mirror shock-absorbing mechanism toinclude a first biaser which biases the mirror-advancing shock-absorbingmember in a direction opposite to the second pressing-moving direction;and a second biaser which biases the mirror-retracting shock-absorbingmember in a direction opposite to the first pressing-moving direction.The mirror-retracting shock-absorbing member is linearly movable along aplane substantially orthogonal to an axis of rotation of the movablemirror. The mirror-advancing shock-absorbing member is rotatable about ashaft substantially parallel to the axis of rotation of the movablemirror. The movable mirror shock-absorbing mechanism further includes arotational limit portion which limits rotational movement of themirror-advancing shock-absorbing member in the biasing direction of thefirst biaser to hold the mirror-advancing shock-absorbing member in thelimit position.

It is desirable for the mirror-advancing shock-absorbing member toinclude a movement restricting portion which projects outwardly in aradial direction of the shaft. The movement restricting portion movesinto a path of movement of a restricted portion formed on themirror-retracting shock-absorbing member to restrict movement of themirror-retracting shock-absorbing member in the biasing direction of thesecond biaser by engagement of the movement restricting portion with therestricted portion when the mirror-advancing shock-absorbing member isin the limit position. A rotation of the mirror-advancingshock-absorbing member from the limit position in a direction oppositeto the biasing direction of the first biaser causes the movementrestricting portion to retract from the path of movement of therestricted portion to release the restriction of the movement of themirror-retracting shock-absorbing member in the biasing direction of thesecond biaser.

It is desirable for the movement restricting portion of themirror-advancing shock-absorbing member to include a slide contactsurface which contacts the restricted portion by the biasing force ofthe first biaser during movement of the mirror-retractingshock-absorbing member when the mirror-retracting shock-absorbing membercomes into contact with and is pressed and moved by the movable mirror.The mirror-retracting shock-absorbing member is pressed and moved by themovable mirror while the restricted portion is in sliding contact withthe slide contact surface.

It is desirable for the camera to include a mirror box whichaccommodates and supports the movable mirror between a pair oflaterally-opposed side walls, wherein the mirror-retractingshock-absorbing member and the mirror-advancing shock-absorbing memberare supported by one of the pair of side walls of the mirror box, andthe rotational limit portion is formed on the one of the pair of sidewalls of the mirror box.

It is desirable for the camera to include a mirror box whichaccommodates and supports the movable mirror, wherein the first biaserincludes a torsion spring which is engaged with the mirror box and themirror-advancing shock-absorbing member, and the second biaser includesan extension spring which is engaged with the mirror box and themirror-retracting shock-absorbing member.

It is desirable for the camera to include a mirror box whichaccommodates and supports the movable mirror, wherein the first biaserincludes a torsion spring which is engaged with the mirror box and themirror-advancing shock-absorbing member, and the second biaser includesa torsion spring which is engaged with the mirror box and themirror-retracting shock-absorbing member.

In an embodiment, a movable mirror shock-absorbing mechanism of a camerais provided, including a movable mirror which is supported to be movablebetween a viewfinder light-guiding position, in which the movable mirroris positioned in a photographing optical path to reflect incident lightfrom an object toward a viewfinder optical system, and a retractedposition, in which the movable mirror is retracted from thephotographing optical path to allow the object light to travel toward aphotographic light-receiving medium; a first shock-absorbing memberwhich comes into contact with, and is pressed and moved by, the movablemirror to absorb shock of the movable mirror when the movable mirrorrotates in one direction between the retracted position and theviewfinder light-guiding position; and a second shock-absorbing memberwhich comes into contact with, and is pressed and moved by, the movablemirror to absorb shock of the movable mirror when the movable mirrorrotates in the other direction between the viewfinder light-guidingposition and the retracted position. When one of the firstshock-absorbing member and the second shock-absorbing member is pressedand moved in a pressing-moving direction by the movable mirror, theother of the first shock-absorbing member and the second shock-absorbingmember restricts a range of movement of the one of the firstshock-absorbing member and the second shock-absorbing member in adirection opposite to the pressing-moving direction.

According to this structure, at least one of the two shock-absorbingmembers, which absorb shock of the movable mirror when the movablemirror rotates to the viewfinder light-guiding position and theretracted position, respectively, functions to limit the range ofmovement of the other shock-absorbing member in a direction opposite tothe pressing-moving direction, in which the aforementioned oneshock-absorbing member is pressed and moved by the movable mirror, sothat bounding of the movable mirror can be suppressed with a smallnumber of components.

It is desirable for each of the first shock-absorbing member and thesecond shock-absorbing member to be biased by a biasing force to move ina direction opposite to the pressing-moving direction, and wherein, whenone of the first shock-absorbing member and the second shock-absorbingmember is pressed and moved by the movable mirror, the other of thefirst shock-absorbing member and the second shock-absorbing member isheld, by the biasing force, in a limit position in which a range ofmovement of the one of the first shock-absorbing member and the secondshock-absorbing member is limited.

In an embodiment, a movable mirror shock-absorbing mechanism of a camerais provided, including a movable mirror which is supported to berotatable between a viewfinder light-guiding position, in which themovable mirror is positioned in a photographing optical path to reflectincident light from an object toward a viewfinder optical system, and aretracted position, in which the movable mirror is retracted from thephotographing optical path to allow the object light to travel toward aphotographic light-receiving medium; a first mirror-retractingshock-absorbing member which comes into contact with, and is pressed andmoved by, the movable mirror when the movable mirror rotates from theviewfinder light-guiding position to the retracted position; a secondmirror-retracting shock-absorbing member which supports the firstmirror-retracting shock-absorbing member in a manner to allow the firstmirror-retracting shock-absorbing member to move relative to the secondmirror-retracting shock-absorbing member, wherein, when the movablemirror rotates from the viewfinder light-guiding position to theretracted position, firstly the second mirror-retracting shock-absorbingmember moves the first mirror-retracting shock-absorbing member solelyin a pressing-moving direction in which the first mirror-retractingshock-absorbing member is pressed and moved by the movable mirror, andsubsequently the second mirror-retracting shock-absorbing member ismoved with the first mirror-retracting shock-absorbing member in thepressing-moving direction; a biaser which biases each of the firstmirror-retracting shock-absorbing member and the secondmirror-retracting shock-absorbing member in a direction opposite to thepressing-moving direction; and a holder which limits movements of thefirst mirror-retracting shock-absorbing member and the secondmirror-retracting shock-absorbing member in a biasing direction of thebiaser when the first mirror-retracting shock-absorbing member and thesecond mirror-retracting shock-absorbing member are pressed and moved ina direction opposite to the biasing direction of the biaser by themovable mirror which rotates toward the retracted position.

According to this structure, when the movable mirror rotates from theviewfinder light-guiding position to the retracted position, firstly thefirst mirror-retracting shock-absorbing member is solely pressed andmoved, and subsequently the second mirror-retracting shock-absorbingmember that supports the first mirror-retracting shock-absorbing memberis pressed and moved together with the first mirror-retractingshock-absorbing member, so that the space for movement of eachshock-absorbing member is minimized while the duration of theshock-absorbing action by the shock-absorbing members can be extended.Additionally, when the movable mirror rotates to the retracted position,the bouncing actions of the first mirror-retracting shock-absorbingmember and the second mirror-retracting shock-absorbing member can bereduced by the holder. This makes it possible to obtain a movable mirrorshock-absorbing mechanism which is superior in shock-absorbingcapability at the time the movable mirror rotates from the viewfinderlight-guiding position to the retracted position, even though themovable mirror shock-absorbing mechanism is compact in structure.Additionally, it is easy to impose an optimum load on the movable mirrorby independently setting the biasing forces of the firstmirror-retracting shock-absorbing member and the secondmirror-retracting shock-absorbing member, and the degree of freedom inthe setting of the shock-absorbing capability is high.

It is desirable for the holder to include a mirror-advancingshock-absorbing member which is held in a movement limit position inwhich movement of the second mirror-retracting shock-absorbing member inthe biasing direction of the biaser is limited when the movable mirroris in the retracted position, and which comes into contact with and ispressed and moved by the movable mirror from the movement limit positionto absorb shock of the movable mirror and release the limitation to themovement of the second mirror-retracting shock-absorbing member when themovable mirror rotates from the retracted position to the viewfinderlight-guiding position; and an interlocking lock member which is movedin association with movement of the second mirror-retractingshock-absorbing member between a lock position in which movement of thefirst mirror-retracting shock-absorbing member relative to the secondmirror-retracting shock-absorbing member is restricted, and an unlockposition in which the first mirror-retracting shock-absorbing member isallowed to move relative to the second mirror-retracting shock-absorbingmember. The interlocking lock member is held in the lock position whenthe second mirror-retracting shock-absorbing member is in a position inwhich movement thereof is restricted by the mirror-advancingshock-absorbing member. A movement in the biasing direction of thebiaser of the second mirror-retracting shock-absorbing member which isreleased from the restriction in movement thereof by themirror-advancing shock-absorbing member causes the interlocking lockmember to move to the unlock position.

In addition, the holder for the first mirror-retracting shock-absorbingmember and the second mirror-retracting shock-absorbing member can besimplified with a small number of components by configuring the holderof the following two members: an interlocking lock member which allowsthe first mirror-retracting shock-absorbing member to move relative tothe second mirror-retracting shock-absorbing member or prevents thefirst mirror-retracting shock-absorbing member from moving relative tothe second mirror-retracting shock-absorbing member in association withmovement of the second mirror-retracting shock-absorbing member, and amirror-advancing shock-absorbing member which absorbs shock of themovable mirror and releases the limitation of the movement of the secondmirror-retracting shock-absorbing member when the movable mirror rotatesfrom the retracted position to the viewfinder light-guiding position.

It is desirable for each of the first mirror-retracting shock-absorbingmember and the second mirror-retracting shock-absorbing member to belinearly movable along a plane substantially orthogonal to an axis ofrotation of the movable mirror. The interlocking lock member isrotatable about a shaft which is substantially parallel to the axis ofrotation of the movable mirror and includes a radial projection whichprojects in a radial direction of the shaft. The radial projection ispositioned in a path of movement of a restricted portion formed on thefirst mirror-retracting shock-absorbing member to restrict the movementof the first mirror-retracting shock-absorbing member in the biasingdirection of the biaser by engagement of the radial projection with therestricted portion when the interlocking member is in the lock position.The radial projection retracts from the path of movement of therestricted portion to allow the first mirror-retracting shock-absorbingmember to move in the biasing direction of the biaser when theinterlocking lock member moves to the unlock position from the lockposition.

It is desirable for the camera to include a mirror box whichaccommodates and supports the movable mirror between a pair oflaterally-opposed side walls, wherein the first mirror-retractingshock-absorbing member and the second mirror-retracting shock-absorbingmember are supported on one of the pair of side walls of the mirror box.The biaser includes a first spring which is engaged with the mirror boxand the first mirror-retracting shock-absorbing member; and a secondspring which is engaged with the mirror box and the secondmirror-retracting shock-absorbing member.

It is desirable for the movable mirror shock-absorbing mechanism toincluding a rotational biaser which biases and rotates themirror-advancing shock-absorbing member toward the movement limitposition. The mirror-advancing shock-absorbing member is rotatable abouta shaft which is substantially parallel to an axis of rotation of themovable mirror. The movable mirror presses the mirror-advancingshock-absorbing member against a biasing force of the rotational biaserwhen the movable mirror rotates to the viewfinder light-guidingposition.

It is desirable for the second mirror-retracting shock-absorbing memberto include a locking portion which defines a movement limit of thesecond mirror-retracting shock-absorbing member in the biasing directionof the biaser by engagement with a fixed member; and arotation-restricting portion which moves into a path of rotationalmovement of the mirror-advancing shock-absorbing member to prevent themirror-advancing shock-absorbing member from rotating to the movementlimit position when the second mirror-retracting shock-absorbing membermoves to a position to make the locking portion contact the fixedmember, and which retracts from the path of rotational movement of themirror-advancing shock-absorbing member to allow the mirror-advancingshock-absorbing member to rotate when the second mirror-retractingshock-absorbing member is pressed and moved with the firstmirror-retracting shock-absorbing member by the movable mirror in adirection opposite to the biasing direction of the biaser.

It is desirable for the mirror-advancing shock-absorbing member toinclude a rotationally restricted surface which comes into contact withthe rotation-restricting portion of the second mirror-retractingshock-absorbing member to be prevented from rotating to the movementlimit position; and a rotation allowance surface which is positionedradially outside of the rotationally restricted surface, wherein, whenthe mirror-advancing shock-absorbing member is in the movement limitposition, the rotation allowance surface contacts the secondmirror-retracting shock-absorbing member to restrict movement of thesecond mirror-retracting shock-absorbing member in the biasing directionof the biaser and to allow the mirror-advancing shock-absorbing memberto rotate.

Additionally, a further simplification of the structure of the movablemirror shock-absorbing mechanism becomes possible by limiting rotationalmovement of the mirror-advancing shock-absorbing member by the secondmirror-retracting shock-absorbing member when the movable mirror rotatesto the viewfinder light-guiding position, contrary to when the movablemirror rotates to the retracted position.

In an embodiment, a movable mirror shock-absorbing mechanism of a camerais provided, including a movable mirror which is supported to berotatable between a viewfinder light-guiding position, in which themovable mirror is positioned in a photographing optical path to reflectincident light from an object toward a viewfinder optical system, and aretracted position, in which the movable mirror is retracted from thephotographing optical path to allow the object light to travel toward aphotographic light-receiving medium; a first shock-absorbing memberwhich comes into contact with and is pressed and moved by the movablemirror when the movable mirror rotates in one direction between theviewfinder light-guiding position and the retracted position; a secondshock-absorbing member which supports the first shock-absorbing memberin a manner to allow the first shock-absorbing member to move relativeto the second shock-absorbing member, wherein, when the movable mirrorrotates in the one direction, firstly the second shock-absorbing membermoves the first shock-absorbing member solely in a pressing-movingdirection in which the first shock-absorbing member is pressed and movedby the movable mirror, and subsequently the second shock-absorbingmember is moved with the first shock-absorbing member in thepressing-moving direction; a biaser which biases each of the firstshock-absorbing member and the second shock-absorbing member in adirection opposite to the pressing-moving direction; and a holder whichlimits movements of the first shock-absorbing member and the secondshock-absorbing member in a biasing direction of the biaser when thefirst shock-absorbing member and the second shock-absorbing member arepressed and moved by the movable mirror in a direction opposite to thebiasing direction of the biaser.

Technical ideas of the present invention can be applied to either casewhere the movable mirror rotates in one direction or the otherdirection; according to the second embodiment of the movable mirrorshock-absorbing mechanism, similar effects can be obtained even if therotation directions of the movable mirror are reversed to those in thefirst embodiment of the movable mirror shock-absorbing mechanism.

It is desirable for the holder to include a third shock-absorbing memberwhich is held in a movement limit position in which movement of thesecond shock-absorbing member in the biasing direction of the biaser islimited when the movable mirror rotates in the one direction to pressand move the first shock-absorbing member and the second shock-absorbingmember, and which comes into contact with, and is pressed and moved by,the movable mirror from the movement limit position to release thelimitation of the movement of the second shock-absorbing member and toabsorb shock of the movable mirror when the movable mirror rotates in adirection opposite to the one direction; and an interlocking lock memberwhich is moved in association with movement of the secondshock-absorbing member between a lock position in which the firstshock-absorbing member is prevented from moving relative to the secondshock-absorbing member and an unlock position in which the firstshock-absorbing member is allowed to move relative to the secondshock-absorbing member. The interlocking lock member is held in the lockposition when the second shock-absorbing member is in a position inwhich movement thereof is restricted by the third shock-absorbingmember. A movement in the biasing direction of the biaser of the secondshock-absorbing member which is released from limitation of movementthereof by the third shock-absorbing member causes the interlocking lockmember to move to the unlock position.

In an embodiment, a movable mirror shock-absorbing mechanism of a camerais provided, including a movable mirror which is supported to berotatable between a viewfinder light-guiding position, in which themovable mirror is positioned in a photographing optical path to reflectincident light from an object toward a viewfinder optical system, and aretracted position, in which the movable mirror is retracted from thephotographing optical path to allow the object light to travel toward aphotographic light-receiving medium; a first shock-absorbing memberwhich is held at a first shock-absorbing standby position by a firstbiaser, so that when the movable mirror rotates from the retractedposition to the viewfinder light-guiding position, the firstshock-absorbing member absorbs shock of the movable mirror by abuttingand being pressed by the movable mirror so that the firstshock-absorbing member moves against a biasing force of the firstbiaser; a second shock-absorbing member which is held at a secondshock-absorbing standby position by a second biaser, so that when themovable mirror rotates from the viewfinder light-guiding position to theretracted position, the second shock-absorbing member absorbs shock ofthe movable mirror by abutting and being pressed by the movable mirrorso that the second shock-absorbing member moves against a biasing forceof the second biaser; and an auxiliary pressing member which is providedon at least one of the first and second shock-absorbing members, whereinthe auxiliary pressing member applies a movement force in the directionof pressing movement that is applied by the movable mirror from the oneof the first and second shock-absorbing members, which is returnedtoward the shock-absorbing standby position by the biasing force of theone of the first and second biasers, against the other of the first andsecond shock-absorbing members that is movably pressed by the movablemirror.

It is desirable for the auxiliary pressing member to include a firstsliding contact surface provided on the first shock-absorbing member,the first sliding contact surface applying a component force in thedirection of pressing movement that is applied by the movable mirroragainst the second shock-absorbing member upon the first sliding contactsurface abutting against the second shock-absorbing member by thebiasing force of the first biaser so as to slide along the abuttingsurfaces therebetween, while the second shock-absorbing member ismovably pressed by the movable mirror; and a second sliding contactsurface provided on the second shock-absorbing member, the secondsliding contact surface applying a component force in the direction ofpressing movement that is applied by the movable mirror against thefirst shock-absorbing member upon the second sliding contact surfaceabutting against the first shock-absorbing member by the biasing forceof the second biaser so as to slide along the abutting surfacestherebetween, while the first shock-absorbing member is movably pressedby the movable mirror.

It is desirable for the first shock-absorbing member to be provided witha first movement control member which enters into a position whichrestricts movement of the second shock-absorbing member toward thesecond shock-absorbing standby position thereof when the firstshock-absorbing member is held at the first shock-absorbing standbyposition by the first biaser, and wherein the first sliding contactsurface is formed as part of an outer surface of the first movementcontrol member; and for the second shock-absorbing member to be providedwith a second movement control member which enters into a position whichrestricts movement of the first shock-absorbing member toward the firstshock-absorbing standby position thereof when the second shock-absorbingmember is held at the second shock-absorbing standby position by thesecond biaser, and wherein the second sliding contact surface is formedas part of an outer surface of the second movement control member.

It is desirable for the first shock-absorbing member to be rotatableabout a rotational axis that is substantially parallel to a rotationalaxis of the movable mirror, wherein the first sliding contact surface isinclined with respect to a rotational direction of the firstshock-absorbing member. The second shock-absorbing member is linearlymovable in a plane which is substantially orthogonal to the rotationalaxis of the movable mirror, wherein the second sliding contact surfaceis inclined with respect to the linear movement of the secondshock-absorbing member.

The present disclosure relates to subject matter contained in JapanesePatent Application Nos. 2010-206045 (filed on Sep. 14, 2010),2010-206046 (filed on Sep. 14, 2010), 2010-206047 (filed on Sep. 14,2010) and 2011-190289 (filed on Sep. 1, 2011) which are expresslyincorporated herein by reference in their entireties.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be described below in detail with referenceto the accompanying drawings in which:

FIG. 1 is a diagram showing a schematic representation of the opticalsystem of an SLR camera according to the present invention;

FIG. 2 is a front perspective view of a mirror box unit of the SLRcamera in a mirror-down state

FIG. 3 is a front perspective view of the mirror box unit in a mirror-upstate;

FIG. 4 is a front perspective view of the mirror box unit in themirror-up state, viewed from a different angle;

FIG. 5 is a rear perspective view of the mirror box unit in themirror-down state;

FIG. 6 is a rear perspective view of the mirror box unit in themirror-down state which is equipped with a first embodiment of a mirrorshock-absorbing mechanism;

FIG. 7 is a rear perspective view of the mirror box unit in themirror-up state which is equipped with the first embodiment of themirror shock-absorbing mechanism;

FIG. 8 is a rear perspective view of the first embodiment of the mirrorshock-absorbing mechanism, showing a state where a contact portion of amirror seat is in contact with a shock-absorbing pin of a mirror-downshock-absorbing lever;

FIG. 9 is a rear perspective view of the first embodiment of the mirrorshock-absorbing mechanism, showing a state where the contact portion ofthe mirror seat is in contact with a shock-absorbing pin of a mirror-upshock-absorbing lever;

FIG. 10 is a left side elevational view of the mirror box unit with aretaining plate removed to expose the first embodiment of the mirrorshock-absorbing mechanism;

FIG. 11 is a side elevational view of the first embodiment of the mirrorshock-absorbing mechanism in the mirror-down state;

FIG. 12 is a side elevational view of the first embodiment of the mirrorshock-absorbing mechanism in a state where the movable mirror is in theprocess of rotating to the mirror-up position from the mirror-downposition;

FIG. 13 is a side elevational view of the first embodiment of the mirrorshock-absorbing mechanism in the mirror-up state;

FIG. 14 is a side elevational view of the first embodiment of the mirrorshock-absorbing mechanism in a state where the movable mirror is in theprocess of rotating to the mirror-down position from the mirror-upposition;

FIG. 15 is a side elevational view of the first embodiment of the mirrorshock-absorbing mechanism in a state where the movable mirror hasrotated from the mirror-up position to the mirror-down position and themirror-down shock-absorbing lever has been rotated into an overrunrange, ahead of a rotational limit position defined by the mirror-upshock-absorbing lever;

FIG. 16 is a side elevational view of a second embodiment of the mirrorshock-absorbing mechanism in the mirror-down state;

FIG. 17 is a side elevational view of the second embodiment of themirror shock-absorbing mechanism in the mirror-up state;

FIG. 18 is a rear perspective view of the mirror box unit in themirror-down state which is equipped with a third embodiment of themirror shock-absorbing mechanism;

FIG. 19 is a rear perspective view of the mirror box unit in themirror-up state which is equipped with the third embodiment of themirror shock-absorbing mechanism;

FIG. 20 is a rear perspective view of the third embodiment of the mirrorshock-absorbing mechanism, showing a state where the contact portion ofthe mirror seat is in contact with the shock-absorbing pin of themirror-down shock-absorbing lever;

FIG. 21 is a rear perspective view of the third embodiment of the mirrorshock-absorbing mechanism, showing a state where the contact portion ofthe mirror seat is in contact with the shock-absorbing pin of themirror-up shock-absorbing lever;

FIG. 22 is a left side elevational view of the mirror box unit shown inFIGS. 18 and 19 with the retaining plate removed to expose the thirdembodiment of the mirror shock-absorbing mechanism;

FIG. 23 is a side elevational view of the third embodiment of the mirrorshock-absorbing mechanism in the mirror-down state;

FIG. 24 is a side elevational view of the third embodiment of the mirrorshock-absorbing mechanism in a state where the movable mirror is in theprocess of rotating to the mirror-up position from the mirror-downposition;

FIG. 25 is a side elevational view of the third embodiment of the mirrorshock-absorbing mechanism in the mirror-up state;

FIG. 26 is a side elevational view of the third embodiment of the mirrorshock-absorbing mechanism in a state where the mirror-up shock-absorbinglever is prevented from moving down by the mirror-down shock-absorbinglever;

FIG. 27 is a side elevational view of the third embodiment of the mirrorshock-absorbing mechanism in a state where the movable mirror hasrotated from the mirror-up position to the mirror-down position and themirror-down shock-absorbing lever has been rotated to a position withinan overrun range, which exceeds a rotational limit position defined bythe mirror-up shock-absorbing lever;

FIG. 28 is a side elevational view of a fourth embodiment of the mirrorshock-absorbing mechanism in the mirror-down state;

FIG. 29 is a side elevational view of the fourth embodiment of themirror shock-absorbing mechanism in the mirror-up state;

FIG. 30 is a rear perspective view of the mirror box unit in themirror-down state which is equipped with a fifth embodiment of themirror shock-absorbing mechanism;

FIG. 31 is a rear perspective view of the mirror box unit in themirror-up state which is equipped with the fifth embodiment of themirror shock-absorbing mechanism;

FIG. 32 is a rear perspective view of the fifth embodiment of the mirrorshock-absorbing mechanism, showing a state where the contact portion ofthe mirror seat is in contact with the shock-absorbing pin of themirror-down shock-absorbing lever;

FIG. 33 is a rear perspective view of the fifth embodiment of the mirrorshock-absorbing mechanism, showing a state where the contact portion ofthe mirror seat is in contact with the shock-absorbing pin of themirror-up shock-absorbing lever;

FIG. 34 is a left side elevational view of the mirror box unit shown inFIGS. 30 and 31 with the retaining plate removed to expose the fifthembodiment of the mirror shock-absorbing mechanism;

FIG. 35 is a side elevational view of the fifth embodiment of the mirrorshock-absorbing mechanism in the mirror-down state;

FIG. 36 is a side elevational view of the fifth embodiment of the mirrorshock-absorbing mechanism in a state where the movable mirror is in theprocess of rotating to the mirror-up position from the mirror-downposition;

FIG. 37 is a side elevational view of the fifth embodiment of the mirrorshock-absorbing mechanism in a state where the movable mirror is in theprocess of rotating to the mirror-up position from the mirror-downposition;

FIG. 38 is a side elevational view of the fifth embodiment of the mirrorshock-absorbing mechanism in the mirror-up state;

FIG. 39 is a side elevational view of the fifth embodiment of the mirrorshock-absorbing mechanism in a state where a release lever is preventedfrom moving by the mirror-down shock-absorbing lever, and the mirror-upshock-absorbing lever is prevented from moving by the lock lever;

FIG. 40 is a side elevational view of the fifth embodiment of the mirrorshock-absorbing mechanism in a state where the movable mirror hasrotated from the mirror-up position to the mirror-down position, and themirror-down shock-absorbing lever has been rotated to a position withinan overrun range, exceeding a rotational limit position defined by themirror-up shock-absorbing lever;

FIG. 41 is a rear perspective view of the mirror box unit in themirror-down state which is equipped with a sixth embodiment of themirror shock-absorbing mechanism;

FIG. 42 is a rear perspective view of the mirror box unit in themirror-up state which is equipped with the sixth embodiment of themirror shock-absorbing mechanism;

FIG. 43 is a rear perspective view of the sixth embodiment of the mirrorshock-absorbing mechanism, showing a state where the contact portion ofthe mirror seat is in contact with the shock-absorbing pin of themirror-down shock-absorbing lever;

FIG. 44 is a rear perspective view of the sixth embodiment of the mirrorshock-absorbing mechanism, showing a state where the contact portion ofthe mirror seat is in contact with the shock-absorbing pin of themirror-up shock-absorbing lever;

FIG. 45 is a left side elevational view of the mirror box unit shown inFIGS. 41 and 42 with the retaining plate removed to expose the sixthembodiment of the mirror shock-absorbing mechanism;

FIG. 46 is a side elevational view of the sixth embodiment of the mirrorshock-absorbing mechanism in the mirror-down state;

FIG. 47 is a side elevational view of the sixth embodiment of the mirrorshock-absorbing mechanism in a state where the movable mirror is in theprocess of rotating to the mirror-up position from the mirror-downposition;

FIG. 48 is a side elevational view of the sixth embodiment of the mirrorshock-absorbing mechanism in a state where the movable mirror is in theprocess of rotating to the mirror-up position from the mirror-downposition;

FIG. 49 is a side elevational view of the sixth embodiment of the mirrorshock-absorbing mechanism in the mirror-up state;

FIG. 50 is a side elevational view of the sixth embodiment of the mirrorshock-absorbing mechanism in a state where the mirror-up shock-absorbinglever is prevented from moving down by the mirror-down shock-absorbinglever; and

FIG. 51 is a side elevational view of the sixth embodiment of the mirrorshock-absorbing mechanism in a state where the movable mirror is in theprocess of rotating to the mirror-down position from the mirror-upposition.

DESCRIPTION OF THE EMBODIMENTS

In the following description of the embodiments, six embodiments of amirror shock-absorbing mechanism will be discussed. First, the structurecommon to all the six embodiments will be discussed hereinafter.

An SLR camera (hereinafter referred simply to as camera) 10 shown inFIG. 1 is provided on the front of a camera body 11 with a lens mount13, to which an interchangeable lens 12 is detachably attached. Thecamera 10 is provided, in the camera body 11 behind the lens mount 13,with a mirror box 14.

The camera 10 is provided inside the mirror box 14 with a movable mirror(quick-return mirror) 15. The movable mirror 15 is constructed such thata main mirror 15 a is fixedly supported on a mirror seat 16, and asub-mirror 17 is positioned behind the mirror seat 16 and rotatablysupported by the mirror seat 16. A pair of mirror seat hinges 16 x whichproject in laterally opposite directions from both sides of the mirrorseat 16 are rotatably supported by both side walls of the mirror box 14,respectively. The camera 10 is provided behind the movable mirror 15with a focal plane shutter (hereinafter referred simply to as shutter)18, and is provided behind the shutter 18 with an image sensor(photographic light-receiving medium) 19. The present embodiment of thecamera 10 is a digital camera using the image sensor 19 as aphotographic light-receiving medium; however, the present invention canalso be applied to a camera using silver-salt film as a photographiclight-receiving medium.

The movable mirror 15 reciprocatively rotates (swings) about the pair ofmirror seat hinges 16 x between a mirror-down position (viewfinderlight-guiding position; shown by solid lines in FIG. 1 and also shown inFIGS. 2, 5, 6, 11, 16, 18, 23, 28, 30, 35, 41 and 46)), in which themovable mirror 15 is positioned in a photographing optical path whichextends from a photographing lens system 12 a provided in theinterchangeable lens 12 to the image sensor 19, to be inclined at anangle of approximately 45 degrees with respect to the photographingoptical path, and an mirror-up position (retracted position; shown byone-dot chain lines in FIG. 1 and also shown in FIGS. 3, 4, 7, 13, 17,19, 25, 29, 31, 38, 42 and 49), in which the movable mirror 15 isretracted upward from the photographing optical path. As shown in FIGS.6, 7, 18, 19, 30, 31, 41 and 42, a mirror-down position defining pin(mirror positioning portion) 20 projects from an inner surface of one ofthe side walls of the mirror box 14 that are positioned on laterallyboth sides of the movable mirror 15, and the mirror-down position of themovable mirror 15 is defined by engagement of the mirror-down positiondefining pin 20 with a stopper 16 a (see FIGS. 8, 9, 20, 21, 32, 33, 43and 44) formed on a side of the mirror seat 16. The installationposition of the mirror-down position defining pin 20 to the mirror box14 can be finely adjusted. In addition, an upper stopper 21 is fixedlyinstalled inside the mirror box 14. An upper surface of the mirror seat16 comes into contact with the upper stopper 21 when the movable mirror15 rotates to the mirror-up position. The camera 10 is provided therein,above the movable mirror 15, with a viewfinder optical system 22 that isconfigured of a pentagonal prism, an eyepiece lens and other opticalelements. Note that all the optical elements of the viewfinder opticalsystem are designated by the same reference numeral 22 in FIG. 1.

Light from an object (object-emanated light) which enters the mirror box14 through the photographing lens system 12 a in the interchangeablelens 12, with the interchangeable lens 12 mounted to the lens mount 13,is reflected by the main mirror 15 a of the movable mirror 15 to beincident on the viewfinder optical system 22 and observable through aviewfinder window 22 a formed in the back of the camera body 11. In thisstate, a photometering operation using a photometering unit 23 which isinstalled behind the pentagonal prism of the viewfinder optical system22 can be carried out. In addition, when the movable mirror 15 is in themirror-down position, the sub-mirror 17 projects obliquely downwardsfrom the underside of the mirror seat 16 to reflect part of theobject-emanated light downward to be incident on a distance measuringunit 24, which makes it possible to detect an object distance. On theother hand, when the movable mirror 15 is in the mirror-up position, theobject-emanated light which enters the mirror box 14 through thephotographing lens system 12 a travels toward the shutter 18 withoutbeing reflected by the movable mirror 15, thus being capable of beingmade incident on the light receiving surface of the image sensor 19 byopening the shutter 18. When the movable mirror 15 is in the mirror-upposition, the sub-mirror 17 is retracted at the underside of the mirrorseat 16. Electronic object images obtained via the image sensor 19 andvarious other information can be displayed on an LCD monitor 25 providedon the back of the camera body 11.

As shown in FIGS. 2 through 5, the camera 10 is provided with a mirrordrive mechanism 30, on a side (left side as viewed from front) of themirror box 14, which drives the movable mirror 15 to rotate the movablemirror 15 up and down. The mirror drive mechanism 30 is provided with amotor 31, a reduction gear train 32 which transmits a driving force ofthe motor 31, a cam gear 33 to which the rotational driving force istransmitted from the reduction gear train 32 via a planetary gearmechanism, and a mirror drive lever 34, the rotational position of whichis controlled by the cam gear 33. The mirror drive lever 34 is supportedby the mirror box 14 to be reciprocatively rotatable (swingable) aboutan axis 34 x, which is substantially parallel to the axis of the pair ofmirror seat hinges 16 x. The mirror drive lever 34 holds a mirror seatboss 16 b which is formed on a side of the mirror seat 16. Pressing themirror seat boss 16 b downward by a holding portion of the mirror drivelever 34 which holds the mirror seat boss 16 b causes the movable mirror15 to rotate downward, toward the mirror-down position, and pressing themirror seat boss 16 b upward by the same holding portion causes themovable mirror 15 to rotate upward, toward the mirror-up position. Themirror drive lever 34 is biased to rotate in a direction to press themovable mirror 15 toward the mirror-down position. When the cam gear 33is located at a specific rotational position, the mirror drive lever 34is pressed and rotated toward the mirror-up position against the biasingforce by a mirror control cam (peripheral surface cam) formed on the camgear 33. More specifically, the cam gear 33 is a single-rotation camgear which is rotated only in one direction from an initial position.When the cam gear 33 is in the initial position, the mirror control camof the cam gear 33 does not press the mirror drive lever 34, so that themovable mirror 15 is held in the mirror-down position by a biasing forcewhich acts on the mirror drive lever 34. A rotation of the cam gear 33partway from the initial position causes the mirror control cam of thecam gear 33 to press and rotate the mirror drive lever 34, which causesthe mirror drive lever 34 to rotate the movable mirror 15 to themirror-up position. During the time the cam gear 33 returns to theinitial position from this partway position, the mirror control cam ofthe cam gear 33 releases the pressure against the mirror drive lever 34,so that the movable mirror 15 returns to the mirror-down position.

The camera 10 is provided on the left side of the mirror box 14, towhich the mirror drive mechanism 30 is installed, with a shutter chargelever 35 which makes the shutter 18 perform a shutter charge operation.In addition to the aforementioned mirror control cam, the cam gear 33 isfurther provided with a shutter charge cam for controlling the operationof the shutter charge lever 35. One rotation of the cam gear 33 from theinitial position causes the shutter charge lever 35 to reciprocativelyrotate to make the shutter 18 perform the shutter charge operation. Theshutter charge operation is not related to the features of the presentinvention, and therefore the detailed description of the shutter chargeoperation will be omitted in the following description.

The camera 10 is provided on the other side of the mirror box 14 (theright side of the mirror box 14 as viewed from front) with a mirrorshock-absorbing mechanism (movable mirror shock-absorbing mechanism)40A, 40B, 40C, 40D, 40E or 40F which absorbs shock of the movable mirror15 that is caused upon rotation of the movable mirror 15 to themirror-down position or the mirror-up position to reduce bouncing(vibration) of the movable mirror 15.

Firstly, a first embodiment of the mirror shock-absorbing mechanism 40Awill be hereinafter discussed with reference to FIGS. 6 through 15. Themirror shock-absorbing mechanism 40A is provided with a mirror-downshock-absorbing lever (mirror-advancing shock-absorbing member) 41, amirror-down shock-absorbing spring (first biaser/an element of anengaging mechanism) 42, a mirror-up shock-absorbing lever(mirror-retracting shock-absorbing member) 43 and a mirror-upshock-absorbing spring (second biaser/an element of the engagingmechanism) 44. The mirror-down shock-absorbing lever 41, the mirror-downshock-absorbing spring 42, the mirror-up shock-absorbing lever 43 andthe mirror-up shock-absorbing spring 44 are held so as not to come offthe mirror box 14 by a retaining plate 48 (see FIG. 6) fixed to a sideof the mirror box 14.

The mirror-down shock-absorbing lever 41 is rotatably supported by ashaft (rotational axis) 41 x which projects from the mirror box 14 andis substantially parallel to the pair of mirror seat hinges 16 x. Themirror-down shock-absorbing lever 41 is substantially sector shaped withits axis of curvature coincident with the shaft 41 x. The mirror-downshock-absorbing lever 41 is provided in the vicinity of the outer edgeof the sector with a shock-absorbing pin (protruded contact portion) 41a which projects into the inside of the mirror box 14, and mirror-downshock-absorbing lever 41 is provided in the vicinity of the shaft 41 xwith a rotationally restricted surface (an element of the engagingmechanism/engaging surface) 41 b which extends in a radial direction ofthe shaft 41 x. In addition, the mirror-down shock-absorbing lever 41 isprovided with a rotation allowance surface 41 c in the shape of an arcabout the shaft 41 x. The rotation allowance surface 41 c is formedcontinuously with the rotationally restricted surface 41 b and ispositioned radially outside of the rotationally restricted surface 41 b.The mirror box 14 is provided, in the right side wall as viewed from thefront, with an arc-shaped through-hole 14 a having axis of curvaturecoincident with the shaft 41 x, and the shock-absorbing pin 41 a of themirror-down shock-absorbing lever 41 is inserted into the through-hole14 a to project into the mirror box 14 (see FIGS. 2, 3, 5 and 10). Theshock-absorbing pin 41 a is positioned in the path of movement of ashock-absorbing contact portion 16 c formed on a side of the mirror seat16 in the vicinity of the free end thereof (i.e., in the path ofrotational movement of the movable mirror 15 about the pair of mirrorseat hinges 16 x) to be contactable with a lower surface of theshock-absorbing contact portion 16 c.

The mirror-down shock-absorbing spring 42 is a torsion spring which isprovided with a coil portion 42 a, a spring arm portion 42 b and aspring arm portion 42 c. The coil portion 42 a surrounds the shaft 41 x,the spring arm portion 42 b is engaged with a spring hook 14 b formed ona side of the mirror box 14, and the spring arm portion 42 c is engagedwith a spring hook 41 d formed on the mirror-down shock-absorbing lever41. The mirror-down shock-absorbing lever 41 is biased clockwise withrespect to FIGS. 10 through 15 by the mirror-down shock-absorbing spring42. The direction of biasing the mirror-down shock-absorbing lever 41 bythe mirror-down shock-absorbing spring 42 is a direction which bringsthe shock-absorbing pin 41 a close to (to bring into contact with) theshock-absorbing contact portion 16 c of the mirror seat 16, and arotational limit projection (first limit portion) 14 c which defines arotational limit of the mirror-down shock-absorbing lever 41 in theaforementioned basing direction projects from a side of the mirror box14. This rotational limit of the mirror-down shock-absorbing lever 41,in which the mirror-down shock-absorbing lever 41 comes in contact withthe rotational limit projection 14 c, will be hereinafter referred to as“shock-absorbing standby position.” The mirror-down shock-absorbinglever 41 is rotatable in a direction away from the rotational limitprojection 14 c against the biasing force of the mirror-downshock-absorbing spring 42 with the shock-absorbing standby position asone of the two rotational limits of the mirror-down shock-absorbinglever 41. Until reaching a predetermined position (corresponding to themirror-down position of the movable mirror 15) with the shock-absorbingstandby position shown in FIGS. 13 and 14 as a starting point, themirror-down shock-absorbing lever 41 is rotated against the biasingforce of the mirror-down shock-absorbing spring 42 while being pressedby the shock-absorbing contact portion 16 c of the movable mirror 15(the mirror seat 16) rotating toward the mirror-down position. Upon themovable mirror 15 reaching the mirror-down position, the stopper 16 a ofthe mirror seat 16 comes into contact with the mirror-down positiondefining pin 20 to thereby be prevented the movable mirror 15 fromrotating further, so that no more pressing force is exerted on themirror-down shock-absorbing lever 41 from the shock-absorbing contactportion 16 c. This range of rotation of the mirror-down shock-absorbinglever 41, in which the mirror-down shock-absorbing lever 41 receives apressing and moving force from the movable mirror 15, will behereinafter referred to as “shock-absorbing moving range.” Themirror-down shock-absorbing lever 41 can further rotate into an overrunrange which exceeds this shock-absorbing moving range. FIGS. 11 and 15show a state where the mirror-down shock-absorbing lever 41 is in theoverrun range. In this state, the movable mirror 15 is prevented fromrotating further from the mirror-down position by engagement with themirror-down position defining pin 20, whereas the mirror-downshock-absorbing lever 41 is disengaged at the shock-absorbing pin 41 athereof from the shock-absorbing contact portion 16 c of the mirror seat16, thus being released from the contact engagement with the movablemirror 15.

The mirror-up shock-absorbing lever 43 is provided with two guide holes43 a and 43 b into which two guide pins, i.e., an upper guide pin 14 dand a lower guide pin (second limit portion) 14 e which are formed on aside of the mirror box 14 to project therefrom, are respectivelyinserted. The mirror-up shock-absorbing lever 43 is supported and guidedlinearly in the vertical direction by the engagement of the guide pins14 d and 14 e with the guide holes 43 a and 43 b, respectively. Thislinear moving direction of the mirror-up shock-absorbing lever 43 is setin a plane substantially orthogonal to the axis of the shaft 41 x of themirror-down shock-absorbing lever 41. In other words, the mirror-downshock-absorbing lever 41 and the mirror-up shock-absorbing lever 43 aresupported to be rotatable and movable along mutually parallel planes,respectively. The mirror-up shock-absorbing lever 43 is provided in thevicinity of the upper end thereof with a shock-absorbing pin (protrudedcontact portion) 43 c which projects into the mirror box 14 and isfurther provided in the vicinity of the lower end of the mirror-upshock-absorbing lever 43 with a spring hook 43 d. The mirror box 14 isprovided, in the right side wall as viewed from the front, with athrough-hole 14 f elongated in the vertical direction, and theshock-absorbing pin 43 c of the mirror-up shock-absorbing lever 43 isinserted into the through-hole 14 f to project into the mirror box 14(see FIGS. 2, 3, 4 and 10). The shock-absorbing pin 43 c is positionedin the movement path of the shock-absorbing contact portion 16 c of themirror seat 16 (i.e., in the path of the rotational movement of themovable mirror 15 about the pair of mirror seat hinges 16 x) to becontactable with an upper surface of the shock-absorbing contact portion16 c. The mirror-up shock-absorbing lever 43 is provided on a sidethereof with a rotation-restricting arm (rotation-restricting portion/anelement of the engaging mechanism/movement restricting portion) 43 ewhich projects rearwardly. The rotation-restricting arm 43 e projects ina direction substantially orthogonal to the vertical direction, i.e.,the moving direction of the mirror-up shock-absorbing lever 43, and aportion of the rotation-restricting arm 43 e in the vicinity of the rearend (right end with respect to FIG. 10) thereof is bent downward andshaped into a hook.

The mirror-up shock-absorbing spring 44 is configured from an extensionspring. The mirror-up shock-absorbing spring 44 is hooked at one end andthe other end thereof onto the spring hook 43 d, which is formed on themirror-up shock-absorbing lever 43, and a spring hook 14 g, which isformed on a side of the mirror box 14, respectively, to bias themirror-up shock-absorbing lever 43 downward. This direction of biasingthe mirror-up shock-absorbing lever 43 by the mirror-up shock-absorbingspring 44 is a direction which brings the shock-absorbing pin 43 c closeto (to bring into contact with) the shock-absorbing contact portion 16 cof the mirror seat 16, and the engagement of the upper end of the guidehole 43 b with the guide pin 14 e prevents the mirror-up shock-absorbinglever 43 from moving further in the biasing direction of the mirror-upshock-absorbing spring 44. This movement limit of the mirror-upshock-absorbing lever 43 in the biasing direction of the mirror-upshock-absorbing spring 44 (in the downward direction) will behereinafter referred to as “shock-absorbing standby position.” When themirror-up shock-absorbing lever 43 is in the shock-absorbing standbyposition, the rotation-restricting arm 43 e has moved into therotational movement path of the rotationally restricted surface 41 b ofthe mirror-down shock-absorbing lever 41 about the shaft 41 x andprevents the mirror-down shock-absorbing lever 41 from rotating in thebiasing direction of the mirror-down shock-absorbing spring 42 byengagement of a side of the rotation-restricting arm 43 e with therotationally restricted surface 41 b (see FIGS. 11 and 12). Morespecifically, it is possible for the rotationally restricted surface 41b of the mirror-down shock-absorbing lever 41 and a side of therotation-restricting arm 43 e of the mirror-up shock-absorbing lever 43which face each other to come in contact with each other only when themirror-up shock-absorbing lever 43 and the mirror-down shock-absorbinglever 41 are in the shock-absorbing standby position and theaforementioned overrun range, respectively. Accordingly, when themirror-down shock-absorbing lever 41 is prevented from rotating byengagement of the rotationally restricted surface 41 b with therotation-restricting arm 43 e of the mirror-up shock-absorbing lever 43,the mirror-down shock-absorbing lever 41 is held in the overrun range,in which the shock-absorbing pin 41 a is disengaged from theshock-absorbing contact portion 16 c of the mirror seat 16. Whereas, ina state (shown in FIG. 13) where the end of the rotation-restricting arm43 e is positioned out of the path of rotational movement of therotationally restricted surface 41 b, the holding of the mirror-downshock-absorbing lever 41 in the overrun range is released, which enablesthe mirror-down shock-absorbing lever 41 to rotate by the mirror-downshock-absorbing spring 42 in the biasing direction thereof (toward theshock-absorbing standby position of the mirror-down shock-absorbinglever 41). In addition, in a state (shown in FIG. 14) where the end ofthe rotation-restricting arm 43 e abuts against the rotation allowancesurface 41 c, the mirror-down shock-absorbing lever 41 is allowed torotate with the rotation allowance surface 41 c that is in slidablecontact with the rotation-restricting arm 43 e.

Operations of the mirror shock-absorbing mechanism 40A will behereinafter discussed with reference to FIGS. 11 through 15. FIG. 11shows a state where the movable mirror 15 is in the mirror-downposition. In this state, the movable mirror 15 is held in themirror-down position with the mirror seat boss 16 b pressed downward bythe mirror drive lever 34, which serves as an element of the mirrordrive mechanism 30, to make the stopper 16 a of the mirror seat 16 abutagainst the mirror-down position defining pin 20. The mirror-upshock-absorbing lever 43 is held in the shock-absorbing standby positionby the biasing force of the mirror-up shock-absorbing spring 44, andprevents the mirror-down shock-absorbing lever 41 from rotating in thebiasing direction of the mirror-down shock-absorbing spring 42 (i.e., inthe clockwise direction with respect to FIGS. 10 through 15) by makingthe rotation-restricting arm 43 e contact the rotationally restrictedsurface 41 b. At this stage, the mirror-down shock-absorbing lever 41 ispositioned in the overrun range, in which the shock-absorbing pin 41 ais disengaged from the shock-absorbing contact portion 16 c of themirror seat 16 in a mirror-down direction (counterclockwise directionwith respect to FIG. 11). Accordingly, the mirror-down shock-absorbinglever 41 does not playa role in the positioning of the mirror seat 16,thus not interfering with the positioning of the mirror seat 16, whichis defined by the engagement of the mirror-down position defining pin 20with the stopper 16 a. More specifically, the stopper 16 a and theshock-absorbing contact portion 16 c, which are respectively formed onthe laterally opposite sides of the mirror seat 16, are positioned to besubstantially bilaterally symmetrical in the widthwise direction of themirror seat 16, and hence are shown overlaying each other as viewed froma side of the mirror seat 16 in FIGS. 11 through 15. In addition, themirror-down shock-absorbing lever 41, which is prevented from rotatingby the mirror-up shock-absorbing lever 43, locates the shock-absorbingpin 41 a at a position advanced from the position of the mirror-downposition defining pin 20 in a mirror-down direction (counterclockwisedirection with respect to FIG. 11). With this relative positionalrelationship between the mirror-down position defining pin 20 and theshock-absorbing pin 41 a, a state in which the mirror-down positiondefining pin 20 is in contact with the stopper 16 a while theshock-absorbing pin 41 a is not in contact with the shock-absorbingcontact portion 16 c (a state in which the mirror-down shock-absorbinglever 41 is in the overrun range) is obtained.

When the movable mirror 15 is rotated from the mirror-down positiontoward the mirror-up position by the mirror drive lever 34 of the mirrordrive mechanism 30, this rotation of the movable mirror 15 causes anupper surface of the shock-absorbing contact portion 16 c of the mirrorseat 16 to come into contact with the shock-absorbing pin 43 c of themirror-up shock-absorbing lever 43 as shown in FIG. 12. At the instanceshown in FIG. 12, the movable mirror 15 has not yet reached themirror-up position; during the rotation of the movable mirror 15 to themirror-up position shown in FIG. 13, the shock-absorbing contact portion16 c of the mirror seat 16 lifts the shock-absorbing pin 43 c to pressand move the mirror-up shock-absorbing lever 43 upward from theshock-absorbing standby position against the biasing force of themirror-up shock-absorbing spring 44. Namely, the spring load of themirror-up shock-absorbing spring 44 is exerted on rotation of themovable mirror 15, and the movable mirror 15 reaches the mirror-upposition while being shock-absorbed (cushioned) by the mirror-upshock-absorbing lever 43 and the mirror-up shock-absorbing spring 44.This suppresses the occurrence of bouncing (vibrations) of the movablemirror 15 when the movable mirror 15 rotates from the mirror-downposition to the mirror-up position. Specifically, the duration of thebouncing of the movable mirror 15 is reduced and the number of bounces(vibrations) of the movable mirror 15 becomes small. When the movablemirror 15 is in the mirror-up position, the engagement of an uppersurface of the mirror seat 16 with the upper stopper 21 prevents themovable mirror 15 from moving further upward (see FIG. 1). Although themirror-up shock-absorbing lever 43 can move up to a position (uppermovement limit thereof) where the lower end of the guide hole 43 a comesinto contact with the guide pin 14 d, the movable mirror 15 comes intocontact with the upper stopper 21 before the mirror-up shock-absorbinglever 43 reaches the upper movement limit. Namely, similar to themirror-down shock-absorbing lever 41, the mirror-up shock-absorbinglever 43 also has an overrun range exceeding the aforementionedshock-absorbing moving range (in which the shock-absorbing pin 43 c ispressed by the shock-absorbing contact portion 16 c of the movablemirror 15 (the mirror seat 16)) in which the shock-absorbing pin 43 c isdisengaged from the shock-absorbing contact portion 16 c of the movablemirror 15 suspended in the mirror-up position by the upper stopper 21.

When the movable mirror 15 rotates toward the mirror-up position, themirror-up shock-absorbing lever 43 is pressed and moved upward from theshock-absorbing standby position by the shock-absorbing contact portion16 c of the mirror seat 16, which causes the rotation-restricting arm 43e to retract upward from the path of rotational movement of therotationally restricted surface 41 b. This releases the prevention ofrotation of the mirror-down shock-absorbing lever 41, so that themirror-down shock-absorbing lever 41 rotates to the shock-absorbingstandby position, in which the mirror-down shock-absorbing lever 41contacts the rotational limit projection 14 c, by the biasing force ofthe mirror-down shock-absorbing spring 42 as shown in FIG. 13. When themirror-down shock-absorbing lever 41 is in the shock-absorbing standbyposition, the shock-absorbing pin 41 a is positioned above themirror-down position defining pin 20, namely, at a position advanced ina mirror-up direction (clockwise direction with respect to FIG. 13) ofthe movable mirror 15 (at a position where the shock-absorbing contactportion 16 c of the mirror seat 16 and the shock-absorbing pin 41 a comein contact with each other before the stopper 16 a and the mirror-downposition defining pin 20 come in contact with each other when themovable mirror 15 rotates to the mirror-down position). In addition,when the mirror-down shock-absorbing lever 41 is in the shock-absorbingstandby position, the rotation allowance surface 41 c is positioneddownwardly away from the rotation-restricting arm 43 e of the mirror-upshock-absorbing lever 43.

When the movable mirror 15 rotates from the mirror-up position to themirror-down position by an operation of the mirror drive lever 34 of themirror drive mechanism 30, the mirror-up shock-absorbing lever 43 movesdown toward the shock-absorbing standby position by the biasing force ofthe mirror-up shock-absorbing spring 44 in accordance with the movementof the shock-absorbing contact portion 16 c of the mirror seat 16. Asshown in FIG. 14, upon the mirror-up shock-absorbing lever 43 movingdown by a predetermined moving amount, the lower end of therotation-restricting arm 43 e comes into contact with the rotationallowance surface 41 c of the mirror-down shock-absorbing lever 41,which stops further downward movement of the mirror-up shock-absorbinglever 43 on its way down. Subsequently, as the movable mirror 15approaches the mirror-down position, the shock-absorbing contact portion16 c of the mirror seat 16 comes into contact with the shock-absorbingpin 41 a of the mirror-down shock-absorbing lever 41, as shown in FIG.14, before the stopper 16 a of the mirror seat 16 comes into contactwith the mirror-down position defining pin 20. At this stage, themirror-down shock-absorbing lever 41 is held in the shock-absorbingstandby position by the biasing force of the mirror-down shock-absorbingspring 42, and during the rotation of the movable mirror 15 to themirror-down position shown in FIG. 15, the shock-absorbing contactportion 16 c of the mirror seat 16 depresses the shock-absorbing pin 41a of the mirror-down shock-absorbing lever 41 to rotate the mirror-downshock-absorbing lever 41 counterclockwise with respect to FIG. 14 fromthe shock-absorbing standby position against the biasing force of themirror-down shock-absorbing spring 42. At this stage, the mirror-downshock-absorbing lever 41 can rotate with the rotation allowance surface41 c in sliding contact with the end of the rotation-restricting arm 43e without being restricted by the mirror-up shock-absorbing lever 43.Accordingly, during rotation of mirror-down shock-absorbing lever 41 inthe shock-absorbing moving range that starts from the shock-absorbingstandby position, the spring load of the mirror-down shock-absorbingspring 42 is exerted on the rotation of the movable mirror 15, and themovable mirror 15 reaches the mirror-down position while beingshock-absorbed (cushioned) by the mirror-down shock-absorbing lever 41and the mirror-down shock-absorbing spring 42. Consequently, theoccurrence of bouncing (vibrations) of the movable mirror 15 when themovable mirror 15 rotates from the mirror-up position to the mirror-downposition is suppressed (the duration of the bouncing becomes reduced andthe number of bounces of the movable mirror 15 becomes small).

FIG. 15 shows a state immediately after the movable mirror 15 is rotatedto the mirror-down position. Similar to the state shown in FIG. 11, thestopper 16 a of the mirror seat 16 comes into contact with themirror-down position defining pin 20 to thereby prevent the movablemirror 15 from rotating any further in the mirror-down direction(counterclockwise direction with respect to FIG. 15). As a result of themirror-down shock-absorbing lever 41 having been pressed and rotatedfrom the shock-absorbing standby position, the prevention of movement ofthe mirror-up shock-absorbing lever 43 by engagement of the rotationallowance surface 41 c with the rotation-restricting arm 43 e isreleased, so that the mirror-up shock-absorbing lever 43 has been moveddown to the shock-absorbing standby position by the biasing force of themirror-up shock-absorbing spring 44. This causes therotation-restricting arm 43 e to move into the path of rotationalmovement of the rotationally restricted surface 41 b to again preventthe mirror-down shock-absorbing lever 41 from rotating toward theshock-absorbing standby position (clockwise direction with respect toFIG. 15). More specifically, when the movable mirror 15 rotates to themirror-down position, the mirror-down shock-absorbing lever 41 rotatesby inertia to a position to disengage the rotationally restrictedsurface 41 b from the rotation-restricting arm 43 e beyond theshock-absorbing standby position, i.e., up to the overrun range as shownin FIG. 15. Subsequently, the biasing force of the mirror-downshock-absorbing spring 42 causes the mirror-down shock-absorbing lever41 to return to the position shown in FIG. 11, in which the rotationallyrestricted surface 41 b is brought into contact with therotation-restricting arm 43 e of the mirror-up shock-absorbing lever 43.As described above, as well as the position of the mirror-downshock-absorbing lever 41 shown in FIG. 15, the position of themirror-down shock-absorbing lever 41 shown in FIG. 11 is also in theoverrun position, in which the shock-absorbing pin 41 a is disengagedfrom the shock-absorbing contact portion 16 c, and the mirror-downposition of the movable mirror 15 is defined by the mirror-down positiondefining pin 20. Accordingly, the mirror-down shock-absorbing lever 41serves as a shock-absorbing member in the shock-absorbing moving range,in which the shock-absorbing pin 41 a is brought into contact with theshock-absorbing contact portion 16 c, when the movable mirror 15 rotatestoward the mirror-down position; in addition, in a state where themovable mirror 15 has reached the mirror-down position, the mirror-downshock-absorbing lever 41 is held in a non-contact position (overrunrange) so as not to be in contact with the mirror seat 16, thus notinterfering with the positioning of the movable mirror 15 that isdefined by engagement of the mirror-down position defining pin 20 withthe stopper 16 a.

As described above, in the mirror shock-absorbing mechanism 40A,bouncing of the movable mirror 15 is suppressed by bringing themirror-down shock-absorbing lever 41 and the mirror-up shock-absorbinglever 43 into contact with the shock-absorbing contact portion 16 c ofthe mirror seat 16 when the movable mirror 15 rotates between themirror-down position and the mirror-up position, respectively. Thismakes it possible to prevent the occurrence of image shake when auser/photographer views object images through the viewfinder opticalsystem 22 and also to prevent the occurrence of delay in arithmeticprocessing using the photometering unit 23 and the distance measuringunit 24, thus making it possible to improve the viewing performance ofthe viewfinder and the sequential photographing performance of thecamera 10. Additionally, in the mirror shock-absorbing mechanism 40A,the mirror-up shock-absorbing lever 43, which is used to absorb shock ofthe movable mirror 15 when the movable mirror 15 moves to the mirror-upposition, is also used as a holder which holds the mirror-downshock-absorbing lever 41 (the shock-absorbing pin 41 a) in a non-contactstate with respect to the mirror seat 16 (i.e., holds the mirror-downshock-absorbing lever 41 in the overrun range, in which the mirror-downshock-absorbing lever 41 is not in contact with the mirror seat 16) andwhich ensures the positioning of the movable mirror 15 with highprecision that is defined using the mirror-down position defining pin20. Namely, the mirror-down shock-absorbing lever 41 is made to functionsecurely as a shock-absorbing member when the movable mirror 15 rotatesto the mirror-down position, whereas the mirror-down shock-absorbinglever 41 can be held in a non-contact state with respect to the movablemirror 15 upon the movable mirror 15 reaching the mirror-down positionwith no need to provide any special holding member other than themirror-up shock-absorbing lever 43. Additionally, the biasing forces ofthe mirror-down shock-absorbing spring 42 and the mirror-upshock-absorbing spring 44 are used not only for absorbing shock of themovable mirror 15 but also for engaging the mirror-down shock-absorbinglever 41 and the mirror-up shock-absorbing lever 43 with each other. Theabove described structure contributes to achieving the mirrorshock-absorbing mechanism 40A that is configured of a reduced number ofelements and simple in structure.

A second embodiment of the mirror shock-absorbing mechanism 40B will behereinafter discussed with reference to FIGS. 16 and 17. In the mirrorshock-absorbing mechanism 40B, the mirror-up shock-absorbing spring 44in the first embodiment of the mirror shock-absorbing mechanism 40A isreplaced by a mirror-up shock-absorbing spring 46 configured from atorsion spring which is used as a member (second biaser/an element ofthe engaging mechanism) for biasing the mirror-up shock-absorbing lever43 toward the shock-absorbing standby position. The mirror-upshock-absorbing spring 46 is a torsion spring which is provided with acoil portion 46 a, a spring arm portion 46 b and a spring arm portion 46c. The coil portion 46 a surrounds a support projection 14 h formed on aside of the mirror box 14, the spring arm portion 46 b is engaged with aspring hook 14 i formed on a side of the mirror box 14, and the springarm portion 46 c is engaged with the base of the shock-absorbing pin 43c of the mirror-up shock-absorbing lever 43. The mirror-upshock-absorbing spring 46 biases the mirror-up shock-absorbing lever 43downward. Similar to the first embodiment of the mirror shock-absorbingmechanism 40A, when the movable mirror 15 is in the mirror-down positionthat is shown in FIG. 16, the mirror-up shock-absorbing lever 43 is heldin the shock-absorbing standby position, in which the upper end of theguide hole 43 b is engaged with the guide pin 14 e, by the biasing forceof the mirror-up shock-absorbing spring 46. When the movable mirror 15rotates to the mirror-up position as shown in FIG. 17, this rotation ofthe movable mirror 15 causes the shock-absorbing contact portion 16 c ofthe mirror seat 16 to press the shock-absorbing pin 43 c, which causesthe mirror-up shock-absorbing lever 43 to move upward from theshock-absorbing standby position against the biasing force of themirror-up shock-absorbing spring 46, and thereupon, the mirror-upshock-absorbing lever 43 absorbs shock of the movable mirror 15 andreleases the prevention of rotation of the mirror-down shock-absorbinglever 41. The operating noise of the movable mirror 15 that is causedwhen it is driven between the mirror-down position and the mirror-upposition can be reduced using the mirror-up shock-absorbing spring 46that is configured from a torsion spring.

Although the first embodiment of the mirror shock-absorbing mechanism40A and the second embodiment of the mirror shock-absorbing mechanism40B have each been illustrated as a mechanism for holding themirror-down shock-absorbing lever 41 in a position (in the overrunrange) that is not in contact with the movable mirror 15 when it is inthe mirror-down position, the first embodiment of the mirrorshock-absorbing mechanism 40A and the second embodiment of the mirrorshock-absorbing mechanism 40B can also be each constructed as amechanism for holding a shock-absorbing member (the mirror-upshock-absorbing lever 43) which absorbs shock of the movable mirror 15when the movable mirror 15 moves to the mirror-up position in a position(in the overrun range) that is not in contact with the movable mirror 15when the movable mirror 15 is in the mirror-up position if the abovedescriptions of the first embodiment of the mirror shock-absorbingmechanism 40A and the second embodiment of the mirror shock-absorbingmechanism 40B are read with the terms “the mirror-up position” and “themirror-down position” reversed. Namely, the present invention can beapplied to the holding of the shock-absorbing member at either of themirror-down position (viewfinder light-guiding position) and themirror-up position (retracted position) of the movable mirror.

Additionally, the mirror shock-absorbing mechanism according to thepresent invention can also be structured to be capable of holding eachshock-absorbing member in a position (in the overrun range) so as notcontact the movable mirror at each of the mirror-down position(viewfinder light-guiding position) and the mirror-up position(retracted position) of the movable mirror. In the first and secondembodiments of the mirror shock-absorbing mechanisms, the mirror-upshock-absorbing lever 43 has an overrun range similar to that of themirror-down shock-absorbing lever 41, as de scribed above. Morespecifically, although the position where the lower end of the guidehole 43 a comes in contact with the guide pin 14 d corresponds to theupper movement limit of the mirror-up shock-absorbing lever 43, themovable mirror 15 comes in contact with the upper stopper 21 before themirror-up shock-absorbing lever 43 reaches the upper movement limit, andaccordingly, moving the mirror-up shock-absorbing lever 43 to a positionin the vicinity of the upper movement limit causes the shock-absorbingpin 43 c to be disengaged from the shock-absorbing contact portion 16 cof the mirror seat 16. Furthermore, by additionally providing themirror-down shock-absorbing lever 41 with an engaging portion forholding the mirror-up shock-absorbing lever 43 in the aforementionedposition in the vicinity of the upper movement limit (in the overrunrange) when the movable mirror 15 rotates to the mirror-up position, themirror-up shock-absorbing lever 43 can be held in a non-contact statewith respect to the movable mirror 15 when the movable mirror 15 is inthe mirror-up position. In this case, the mirror-down shock-absorbinglever 41 and the mirror-down shock-absorbing spring 42, each of whichserves as a shock-absorbing member when the movable mirror 15 rotates tothe mirror-down position, also serve as a holder which holds themirror-up shock-absorbing lever 43 in the overrun range so that themirror shock-absorbing mechanism can be structured to have a smallnumber of components and be simple in structure, similar to themechanism for holding the mirror-down shock-absorbing lever 41 in theoverrun range when the movable mirror 15 is in the mirror-down position.

A third embodiment of the mirror shock-absorbing mechanism 40C will behereinafter discussed with reference to FIGS. 18 through 27. The mirrorshock-absorbing mechanism 40C is provided with a mirror-downshock-absorbing lever (mirror-advancing shock-absorbing member) 141, amirror-down shock-absorbing spring (first biaser) 142, a mirror-upshock-absorbing lever (mirror-retracting shock-absorbing member) 143 anda mirror-up shock-absorbing spring (second biaser) 144. The mirror-downshock-absorbing lever 141, the mirror-down shock-absorbing spring 142,the mirror-up shock-absorbing lever 143 and the mirror-upshock-absorbing spring 144 are held so as not to come off the mirror box14 by a retaining plate 148 (see FIG. 18) that is fixed to a side of themirror box 14. The mirror-down shock-absorbing lever 141, themirror-down shock-absorbing spring 142, the mirror-up shock-absorbinglever 143 and the mirror-up shock-absorbing spring 144 correspond to themirror-down shock-absorbing lever 41, the mirror-down shock-absorbingspring 42, the mirror-up shock-absorbing lever 43 and the mirror-upshock-absorbing spring 44 of the first embodiment of the mirrorshock-absorbing mechanism 40A, respectively, and elements of the thirdembodiment of the mirror shock-absorbing mechanism 40C which are thesame as those of the first embodiment of the mirror shock-absorbingmechanism 40A are designated by the same reference numerals and thedetailed description thereof are omitted.

The mirror-down shock-absorbing lever 141 is identical in basicstructure to the mirror-down shock-absorbing lever 41 of each of thefirst and second embodiments of the mirror shock-absorbing mechanisms.The mirror-down shock-absorbing lever 141 is additionally provided witha downward movement restricting arm (movement restricting portion) 41 ewhich projects in a radially outward direction away from the shaft 41 x.As shown in FIG. 21, the downward movement restricting arm 41 e isshaped into a triangular protrusion which extends in a radially outwarddirection from a portion of the rotationally restricted surface 41 b,which constitutes as a base end of the downward movement restricting arm41 e which is located in close vicinity of a side (interior side of themirror box 14) of the mirror box 14. The downward movement restrictingarm 41 e is provided, on one side thereof adjacent to the rotationallyrestricted surface 41 b, with an inclined surface (slide contactsurface) 41 f which is inclined to a radial direction of the shaft 41 x.

The mirror-down shock-absorbing spring 142 is a torsion spring similarto the mirror-down shock-absorbing spring 42 of each of the first andsecond embodiments of the mirror shock-absorbing mechanisms. Themirror-down shock-absorbing spring 142 biases the mirror-downshock-absorbing lever 141 in a direction to rotate toward ashock-absorbing standby position (limit position) in which themirror-down shock-absorbing lever 141 comes in contact with a rotationallimit projection (rotational limit portion) 114 c which projects from aside of the mirror box 14. Although the rotational limit projection 114c is different in shape from the rotational limit projection 14 c ofeach of the first and second embodiments of the mirror shock-absorbingmechanisms, the rotational limit projection 114 c is identical to therotational limit projection 14 c in capability of defining theshock-absorbing standby position of the mirror-down shock-absorbinglever (41/141).

The mirror-up shock-absorbing lever 143 has the same basic structure tothat of the mirror-up shock-absorbing lever 43 of the first and secondembodiments; however, the mirror-up shock-absorbing lever 143 isdifferent from the mirror-up shock-absorbing lever 43 in that the upperguide pin 14 d and the lower guide pin 14 e, which are formed to projectfrom a side of the mirror box 14, are inserted into an elongated guidehole 43 f which is formed through the mirror-up shock-absorbing lever143. Accordingly, a shock-absorbing standby position (limit position) ofthe mirror-up shock-absorbing lever 143 is defined by engagement of theupper end of the guide hole 43 f with the guide pin 14 e. The mirror-upshock-absorbing spring 144 is an extension spring similar to themirror-up shock-absorbing spring 44 of the first embodiment of themirror shock-absorbing mechanism. The mirror-up shock-absorbing spring144 biases the mirror-up shock-absorbing lever 143 toward theaforementioned shock-absorbing standby position, which is defined byengagement of the upper end of the guide hole 43 f with the guide pin 14e.

As shown in FIGS. 20 and 21, the mirror-up shock-absorbing lever 143 isfurther provided with a downward movement restricted projection(restricted portion) 43 g which projects from the end of therotation-restricting arm 43 e in a direction to approach a side of themirror box 14 (toward the inside of the mirror box 14). The downwardmovement restricted projection 43 g lies in a plane in which thedownward movement restricting arm 41 e of the mirror-downshock-absorbing lever 141 lies. The downward movement restrictedprojection 43 g can come into contact with the downward movementrestricting arm 41 e of the mirror-down shock-absorbing lever 141without interfering with any other part of the mirror-downshock-absorbing lever 141 (such as the rotationally restricted surface41 b). Although the downward movement restricted projection 43 g and thedownward movement restricting arm 41 e are formed to be offset in aninner lateral direction of the mirror box 14 from a plane in which therotation-restricting arm 43 e lies in the above described embodimentshown in FIGS. 20 and 21, it is possible for the downward movementrestricted projection 43 g and the downward movement restricting arm 41e be formed outside of the rotation-restricting arm 43 e (i.e., to beoffset in an outer lateral direction of the mirror box 14).

When the mirror-down shock-absorbing lever 141 is in the shock-absorbingstandby position shown in FIGS. 25 and 26, the rotational restrictingarm 41 e has moved into the path of movement of the downward movementrestricted projection 43 g and prevents the mirror-up shock-absorbinglever 143 from moving in the biasing direction of the mirror-upshock-absorbing spring 144 by engagement of the end (tip) of thedownward movement restricting arm 41 e with the downward movementrestricted projection 43 g (see FIG. 26). In a state where therotational restricting arm 41 e and the downward movement restrictedprojection 43 g are engaged with each other, the mirror-downshock-absorbing lever 141 can rotate in a direction opposite to thebiasing direction of the mirror-down shock-absorbing spring 142 (in thecounterclockwise direction with respect to FIG. 26).

Operations of the mirror shock-absorbing mechanism 40C will behereinafter discussed with reference to FIGS. 23 through 27. FIG. 23shows a state where the movable mirror is in the mirror-down position.The mirror-up shock-absorbing lever 143 is held in the shock-absorbingstandby position by the biasing force of the mirror-up shock-absorbingspring 144, and prevents the mirror-down shock-absorbing lever 141 fromrotating in the biasing direction of the mirror-down shock-absorbingspring 142 (i.e., in the clockwise direction with respect to FIG. 23) bybringing the rotation-restricting arm 43 e into contact with therotationally restricted surface 41 b. At this stage, the mirror-downshock-absorbing lever 141 is held at a position in the overrun range, inwhich the shock-absorbing pin 41 a is disengaged from theshock-absorbing contact portion 16 c of the mirror seat 16 in amirror-down direction (counterclockwise direction with respect to FIG.23).

When the movable mirror 15 is rotated from the mirror-down positiontoward the mirror-up position to thereby bring an upper surface of theshock-absorbing contact portion 16 c of the mirror seat 16 into contactwith the shock-absorbing pin 43 c of the mirror-up shock-absorbing lever143 as shown in FIG. 24, and the mirror-up shock-absorbing lever 143 ispressed and moved upward from the shock-absorbing standby positionagainst the biasing force of the mirror-up shock-absorbing spring 144.This suppresses the occurrence of bouncing (vibrations) of the movablemirror 15 when the movable mirror 15 rotates to the mirror-up positionthat is shown in FIG. 25. In a state where the movable mirror 15 is inthe mirror-up position by engagement with the upper stopper 21, themirror-up shock-absorbing lever 143 has not reached the upper movementlimit thereof, at which the lower end of the guide hole 43 f comes incontact with the guide pin 14 d, so that there is still room for themirror-up shock-absorbing lever 143 to move further up into the overrunrange (i.e., to a position to disengage the shock-absorbing pin 43 cfrom the shock-absorbing contact portion 16 c of the movable mirror 15).

When the mirror-up shock-absorbing lever 143 is pressed and moved upwardfrom the shock-absorbing standby position, the rotation-restricting arm43 e retracts upward from the path of rotational movement of therotationally restricted surface 41 b. This releases the prevention ofrotation of the mirror-down shock-absorbing lever 141. However, themirror-down shock-absorbing lever 141 does not rotate to theshock-absorbing standby position by the biasing force of the mirror-downshock-absorbing spring 142 immediately after the rotation-restrictingarm 43 e and the rotationally restricted surface 41 b are disengagedfrom each other, rather, the mirror-down shock-absorbing lever 141 isstopped with the inclined surface 41 f of the downward movementrestricting arm 41 e abutting on a side of the downward movementrestricted projection 43 g of the mirror-up shock-absorbing lever 143.In addition, the mirror-up shock-absorbing lever 143 moves upward whilemaking a side of the downward movement restricted projection 43 g slideon the inclined surface 41 f. In this sliding operation, a holding forceproduced via the mirror-down shock-absorbing lever 141 (the biasingforce of the mirror-down shock-absorbing spring 142) acts on themirror-up shock-absorbing lever 143, so that backlash between the guidehole 43 f and the guide pins 14 d and 14 e is absorbed, which allowssmooth movement of the mirror-up shock-absorbing lever 143 without playand assists shock absorption for the mirror seat 16. Upon the mirror-upshock-absorbing lever 143 being moved to a position to make the downwardmovement restricted projection 43 g disengaged upwardly from thedownward movement restricting arm 41 e, the sliding movement of thedownward movement restricted projection 43 g on the inclined surface 41f is cancelled, and the mirror-down shock-absorbing lever 141 rotates tothe shock-absorbing standby position, in which the mirror-downshock-absorbing lever 141 contacts the rotational limit projection 114c, by the biasing force of the mirror-down shock-absorbing spring 142.When the mirror-down shock-absorbing lever 141 is in the shock-absorbingstandby position, the shock-absorbing pin 41 a is positioned above themirror-down position defining pin 20, namely, at a position advanced ina mirror-up direction (clockwise direction with respect to FIG. 25) ofthe movable mirror 15.

As shown in FIG. 25, when the mirror-down shock-absorbing lever 141 isrotated to the shock-absorbing standby position, the downward movementrestricting arm 41 e is positioned immediately below the downwardmovement restricted projection 43 g of the mirror-up shock-absorbinglever 143. FIG. 25 shows a state where the mirror-up shock-absorbinglever 143 has been moved up by the movable mirror 15 that has rotated tothe mirror-up position to thereby create a slight gap between the end ofthe downward movement restricting arm 41 e and the downward movementrestricted projection 43 g. From this state, a downward movement of themirror-up shock-absorbing lever 143 causes the downward movementrestricted projection 43 g to come into contact with the end (tip) ofthe downward movement restricting arm 41 e as shown in FIG. 26. Assuminga plane P (shown by a one-dot chain line in FIG. 26) which passesthrough the center (rotational center) of the shaft 41 x of themirror-down shock-absorbing lever 141 and is substantially parallel tothe moving direction of the mirror-up shock-absorbing lever 143, acontact point Q (shown in FIG. 26) between the downward movementrestricted projection 43 g and the downward movement restricting arm 41e is offset rightward from the plane P with respect to FIG. 26.Accordingly, the force of the downward movement restricted projection 43g that presses the downward movement restricting arm 41 e acts on themirror-down shock-absorbing lever 141 as a force urging the mirror-downshock-absorbing lever 141 to rotate clockwise with respect to FIG. 26(in the biasing direction of the mirror-down shock-absorbing spring142). Since the mirror-down shock-absorbing lever 141 is prevented fromrotating in this direction by the rotational limit projection 114 c, themirror-down shock-absorbing lever 141 is held in the position shown inFIG. 26. Namely, the position of the downward movement restricting arm41 e of the mirror-down shock-absorbing lever 141 does not change, andengagement of the downward movement restricted projection 43 g with thedownward movement restricting arm 41 e prevents the mirror-upshock-absorbing lever 143 from moving downward.

As described above, when the movable mirror 15 rotates from themirror-down position to the mirror-up position, the spring load of themirror-up shock-absorbing spring 144 is exerted on the rotation of themovable mirror 15 to absorb shock of the movable mirror 15 by engagementof the shock-absorbing contact portion 16 c of the mirror seat 16 withthe shock-absorbing pin 43 c of the mirror-up shock-absorbing lever 143.Additionally, the range of movement (the amount of downward movement) ofthe mirror-up shock-absorbing lever 143 in a state where the movablemirror 15 has reached the mirror-up position is limited to an extremelysmall range by the downward movement restricting arm 41 e of themirror-down shock-absorbing lever 141. This reduces the degree ofrebounding movement of the mirror-up shock-absorbing lever 143, shortensthe duration of bouncing (vibration) of the movable mirror 15 andreduces the number of bounces thereof when the movable mirror 15 rotatesto the mirror-up position. Hence, the shock-absorbing capability for themovable mirror is enhanced.

In a reverse operation to the above described mirror-up operation, whenthe movable mirror 15 approaches the mirror-down position while rotatingfrom the mirror-up position, the shock-absorbing contact portion 16 c ofthe mirror seat 16 comes into contact with the shock-absorbing pin 41 aof the mirror-down shock-absorbing lever 141 before the stopper 16 a ofthe mirror seat 16 comes into contact with the mirror-down positiondefining pin 20. At this stage, the mirror-down shock-absorbing lever141 is held at the shock-absorbing standby position by the biasing forceof the mirror-down shock-absorbing spring 142, and during the time themovable mirror 15 rotates to the mirror-down position shown in FIG. 27,the shock-absorbing contact portion 16 c of the mirror seat 16 depressesthe shock-absorbing pin 41 a of the mirror-down shock-absorbing lever141 to rotate the mirror-down shock-absorbing lever 141 counterclockwisewith respect to FIGS. 25 and 26 from the shock-absorbing standbyposition against the biasing force of the mirror-down shock-absorbingspring 142. Accordingly, during rotation of the mirror-downshock-absorbing lever 141 in the shock-absorbing moving range thatstarts from the shock-absorbing standby position, the spring load of themirror-down shock-absorbing spring 142 is exerted on rotation of themovable mirror 15, and the movable mirror 15 reaches the mirror-downposition while being shock-absorbed (cushioned) by the mirror-downshock-absorbing lever 141 and the mirror-down shock-absorbing spring142.

When the mirror-down shock-absorbing lever 141 is pressed and rotatedcounterclockwise with respect to FIGS. 25 and 26 from theshock-absorbing standby position by a rotation of the movable mirror 15from the mirror-up position to the mirror-down position, the downwardmovement restricting arm 41 e retracts from the path of movement of thedownward movement restricted projection 43 g, which releases therestriction applied to the range of movement of the mirror-upshock-absorbing lever 143 by the mirror-down shock-absorbing lever 141.Therefore, when the movable mirror 15 rotates to the mirror-downposition, the mirror-up shock-absorbing lever 143 is moved down to theshock-absorbing standby position by the biasing force of the mirror-upshock-absorbing spring 144 (see FIG. 27).

FIG. 27 shows a state immediately after the movable mirror 15 is rotatedto the mirror-down position. Similar to the state shown in FIG. 23, thestopper 16 a of the mirror seat 16 comes into contact with themirror-down position defining pin 20 to thereby prevent the movablemirror 15 from rotating in the mirror-down direction (counterclockwisedirection with respect to FIG. 27). As a result of the mirror-downshock-absorbing lever 141 having been pressed and rotated from theshock-absorbing standby position, the restriction applied to the rangeof movement of the mirror-up shock-absorbing lever 143 by themirror-down shock-absorbing lever 141 is released, and the mirror-upshock-absorbing lever 143 has been moved down to the shock-absorbingstandby position by the biasing force of the mirror-up shock-absorbingspring 144 as described above. This causes the rotation-restricting arm43 e to move into the path of rotational movement of the rotationallyrestricted surface 41 b to prevent the mirror-down shock-absorbing lever141 from rotating toward the shock-absorbing standby position (clockwisedirection with respect to FIG. 27). Similar to the mirror-downshock-absorbing lever 41 of the first embodiment of the mirrorshock-absorbing mechanism, when the movable mirror 15 rotates to themirror-down position, the mirror-down shock-absorbing lever 141 rotatesby inertia to the position shown in FIG. 27, and subsequently returns,by the biasing force of the mirror-down shock-absorbing spring 142, tothe position shown in FIG. 23 (into the overrun range, in which theshock-absorbing pin 41 a is disengaged from the shock-absorbing contactportion 16 c of the mirror seat 16), in which the rotationallyrestricted surface 41 b of the mirror-down shock-absorbing lever 141 isbrought into contact with the rotation-restricting arm 43 e of themirror-up shock-absorbing lever 143.

As described above, in the mirror shock-absorbing mechanism 40C, themirror-down shock-absorbing lever 141 that absorbs shock of the movablemirror 15 when the movable mirror 15 rotates to the mirror-down positionalso serves as a device which limits the range of movement of themirror-up shock-absorbing lever 143 that absorbs shock of the movablemirror 15 when the movable mirror 15 rotates to the mirror-up position.Accordingly, it is not necessary to provide any additional member whichlimits the range of movement of the mirror-up shock-absorbing lever 143,so that the mirror shock-absorbing mechanism 40C can be structured tohave a small number of components and be simple in structure, and canefficiently reduce shock when the movable mirror 15 rotates to themirror-up position.

A fourth embodiment of the mirror shock-absorbing mechanism 40D will behereinafter discussed with reference to FIGS. 28 and 29. In the mirrorshock-absorbing mechanism 40D, the mirror-up shock-absorbing spring 144in the third embodiment of the mirror shock-absorbing mechanism 40C isreplaced by a mirror-up shock-absorbing spring 146 which is configuredfrom a torsion spring, similar to the mirror-up shock-absorbing spring46 of the second embodiment of the mirror shock-absorbing mechanism 40B,that is used as a member (second biaser) which biases the mirror-upshock-absorbing lever 143 toward the shock-absorbing standby position.Although the detailed description of the mirror-up shock-absorbingspring 146 will be omitted since the detailed description of themirror-up shock-absorbing spring 146 is identical to that of themirror-up shock-absorbing spring 46, the mirror-up shock-absorbingspring 146 biases the mirror-up shock-absorbing lever 143 downward, andwith this biasing force the mirror-up shock-absorbing lever 143 is heldin the shock-absorbing standby position, in which the upper end of theguide hole 43 f is engaged with the guide pin 14 e, in the mirror-downstate shown in FIG. 28. When the movable mirror 15 rotates to themirror-up position as shown in FIG. 29, this rotation of the movablemirror 15 causes the mirror-up shock-absorbing lever 143 to move upwardfrom the shock-absorbing standby position against the biasing force ofthe mirror-up shock-absorbing spring 146, and thereupon, the mirror-upshock-absorbing lever 143 absorbs shock of the movable mirror 15 andreleases the prevention of rotation of the mirror-down shock-absorbinglever 141.

Although the third embodiment of the mirror shock-absorbing mechanism40C and the fourth embodiment of the mirror shock-absorbing mechanism40D have each been illustrated as a mechanism for limiting the range ofmovement of the mirror-up shock-absorbing lever 143 by the mirror-downshock-absorbing lever 141 when the movable mirror 15 is in the mirror-upposition, the third embodiment of the mirror shock-absorbing mechanism40C and the fourth embodiment of the mirror shock-absorbing mechanism40D can also each be constructed as a mechanism for limiting the rangeof movement of a mirror-down shock-absorbing member (mirror-advancingshock-absorbing member) by a mirror-up shock-absorbing member(mirror-retracting shock-absorbing member) when the movable mirror 15 isin the mirror-down position (viewfinder light-guiding position) if theabove descriptions of the mirror shock-absorbing mechanism 40C and thesecond embodiment of the mirror shock-absorbing mechanism 40D are readwith the terms “the mirror-up position” and “the mirror-down position”reversed.

A fifth embodiment of the mirror shock-absorbing mechanism 40E will behereinafter discussed with reference to FIGS. 30 through 40. Elements ofthe fifth embodiment of the mirror shock-absorbing mechanism which arethe same as those of each of the above described embodiments of themirror shock-absorbing mechanisms are designated by the same referencenumerals and the detailed description of the same elements will beomitted. The mirror shock-absorbing mechanism 40E is provided with amirror-down shock-absorbing lever (holder/mirror-advancingshock-absorbing member/third shock-absorbing member) 241, a mirror-downshock-absorbing spring (rotational biaser) 242, a release lever (secondmirror-retracting shock-absorbing member/second shock-absorbing member)243, a release spring (biaser/second spring) 244, a mirror-upshock-absorbing slider (first mirror-retracting shock-absorbingmember/first shock-absorbing member) 245, a mirror-up shock-absorbingspring (biaser/first spring) 246 and a lock lever (holder/interlockinglock member) 247. Each of these members is held so as not to come offthe mirror box 14 by a retaining plate 248 (see FIG. 30) that is fixedto a side of the mirror box 14.

The mirror-down shock-absorbing lever 241 and the mirror-downshock-absorbing spring 242 correspond to the mirror-down shock-absorbinglever 41 and the mirror-down shock-absorbing spring 42, respectively, ofeach of the first and second embodiments of the mirror shock absorbingmechanisms 40A and 40B. The mirror-down shock-absorbing spring 242 thatis configured from a torsion spring biases and rotates the mirror-downshock-absorbing lever 241 in the clockwise direction with respect toFIGS. 34 through 40, and the rotational limit of the mirror-downshock-absorbing lever 241 in the biasing direction of the mirror-downshock-absorbing spring 242 is defined by the engagement of themirror-down shock-absorbing lever 241 with a rotational limit projection214 c which projects from the mirror box 14. The rotational limitprojection 214 c has the same function as each of the rotational limitprojections 14 c and 114 c of the first through fourth embodiments ofthe mirror shock-absorbing mechanisms, and the rotational limit of themirror-down shock-absorbing lever 241, in which the mirror-downshock-absorbing lever 241 is engaged with the rotational limitprojection 214 c, is a shock-absorbing standby position of themirror-down shock-absorbing lever 241 (movement limit position at whichmovement of the release lever 243 in the biasing direction of therelease spring 244 is limited).

The release lever 243 is provided with a guide hole 243 a and a guidehole (locking portion) 243 b into which the upper guide pin 14 d and thelower guide pin (fixed member) 14 e that are formed on a side of themirror box 14 to project therefrom are inserted, respectively. Therelease lever 243 is supported and guided linearly in the verticaldirection by the engagement of the guide pins 14 d and 14 e with theguide holes 243 a and 243 b, respectively. This linear moving directionof the release lever 243 is set in a plane substantially orthogonal tothe axis of the shaft 41 x of the mirror-down shock-absorbing lever 241.In other words, the mirror-down shock-absorbing lever 241 and therelease lever 243 are supported to be rotatable and movable alongmutually parallel planes, respectively. The release lever 243 isprovided on a side thereof with a rotation-restricting arm(rotation-restricting portion) 243 c which projects rearwardly. Therotation-restricting arm 243 c projects in a direction substantiallyorthogonal to the vertical direction, i.e., the moving direction of therelease lever 243, and a portion of the rotation-restricting arm 243 cin the vicinity of the rear end (right end with respect to FIG. 34)thereof is bent downward to be shaped into a hook. The release lever 243is provided in the vicinity of the lower end thereof with a spring hook243 d.

The release spring 244 is configured from an extension spring. Therelease spring 244 is hooked at one end and the other end thereof ontothe spring hook 243 d, which is formed on the release lever 243, and thespring hook 14 g, which is formed on a side of the mirror box 14,respectively, to bias the release lever 243 downward. The engagement ofthe upper end (locking portion) of the guide hole 243 b with the guidepin 14 e prevents the release lever 243 from moving further downward inthe biasing direction (downward direction) of the release spring 244.This movement limit of the release lever 243 in the biasing direction ofthe release spring 244 (in the downward direction) will be hereinafterreferred to as “rotational limit position.” When the release lever 243is in the rotational limit position, the rotation-restricting arm 243 chas moved into the path of rotational movement of the rotationallyrestricted surface 41 b of the mirror-down shock-absorbing lever 241about the shaft 41 x to prevent the mirror-down shock-absorbing lever241 from rotating in the biasing direction of the mirror-downshock-absorbing spring 242 by engagement of a side of therotation-restricting arm 243 c with the rotationally restricted surface41 b (see FIGS. 35 through 37). More specifically, it is possible forthe rotationally restricted surface 41 b of the mirror-downshock-absorbing lever 241 and a side of the rotation-restricting arm 243c of the release lever 243 to face each other and to come in contactwith each other only when the release lever 243 is in the rotationallimit position and when the mirror-down shock-absorbing lever 241 is inthe overrun range (see FIGS. 35, 36, 37 and 40), in which theshock-absorbing pin 41 a is disengaged from the shock-absorbing contactportion 16 c of the mirror seat 16 in the mirror-down state.Accordingly, when the mirror-down shock-absorbing lever 241 is preventedfrom rotating by the engagement of the rotationally restricted surface41 b with the rotation-restricting arm 243 c of the release lever 243,the mirror-down shock-absorbing lever 241 is held at a position in theoverrun range, in which the shock-absorbing pin 41 a is disengaged fromthe shock-absorbing contact portion 16 c of the mirror seat 16. On theother hand, in a state (shown in FIG. 38) where the end of therotation-restricting arm 243 c is positioned out of the path ofrotational movement of the rotationally restricted surface 41 b, theholding of the mirror-down shock-absorbing lever 241 in the overrunrange is released, which enables the mirror-down shock-absorbing lever241 to rotate by the mirror-down shock-absorbing spring 242 in thebiasing direction thereof (toward the shock-absorbing standby positionof the mirror-down shock-absorbing lever 241). In addition, in a state(shown in FIG. 39) where the end of the rotation-restricting arm 243 cabuts on the rotation allowance surface 41 c, the mirror-downshock-absorbing lever 241 is allowed to rotate with the rotationallowance surface 41 c in slidable contact with the rotation-restrictingarm 243 c.

The release lever 243 is provided with a support guide hole 243 e whichis formed as an elongated through-hole, the lengthwise direction ofwhich is substantially parallel to the moving direction of the releaselever 243. The mirror-up shock-absorbing slider 245 is positioned in thesupport guide hole 243 e and supported by the release lever 243 thereinto be slidably movable in the lengthwise direction of the support guidehole 243 e. The mirror-up shock-absorbing slider 245 is provided with ashock-absorbing pin 245 a which projects into the mirror box 14. Therelease lever 243 is provided with a through-hole 243 f (see FIGS. 34through 40) which is formed at a position that overlaps the through-hole14 f of the mirror box 14 and is elongated in the vertical direction.The through-hole 243 f is communicatively connected to the support guidehole 243 e, and the shock-absorbing pin 245 a of the mirror-upshock-absorbing slider 245 that is supported by the support guide hole243 e is inserted into the through-holes 243 f and 14 f to project intothe mirror box 14 (see FIGS. 2 through 4). The shock-absorbing pin 245 ais positioned in the path of movement of the shock-absorbing contactportion 16 c of the mirror seat 16 (i.e., in the path of rotationalmovement of the movable mirror 15 about the pair of mirror seat hinges16 x) to be contactable with an upper surface of the shock-absorbingcontact portion 16 c. The mirror-up shock-absorbing slider 245 isfurther provided with a lock pin (restricted portion) 245 b whichprojects in a direction opposite to the direction of projection of theshock-absorbing pin 245 a. The shock-absorbing pin 245 a and the lockpin 245 b are substantially coaxial with each other, and theshock-absorbing pin 245 a is positioned behind the lock pin 245 b sothat the lock pin 245 b is seen on top of the shock-absorbing pin 245 ain FIGS. 34 through 40. The mirror-up shock-absorbing slider 245 isfurther provided below the shock-absorbing pin 245 a and the lock pin245 b with a guide hole 245 c which is formed as an elongatedthrough-hole, the lengthwise direction of which is substantiallyparallel to the support guide hole 243 e of the release lever 243 (i.e.,substantially parallel to the moving direction of each of the releaselever 243 and the mirror-up shock-absorbing slider 245). The guide pin14 e that passes through the guide hole 243 b of the release lever 243is inserted into the guide hole 245 c, and the mirror-up shock-absorbingslider 245 is guided by the guide hole 245 c and the guide pin 14 e whenthe mirror-up shock-absorbing slider 245 moves.

The mirror-up shock-absorbing spring 246 is a torsion spring which isprovided with a coil portion 246 a, a spring arm portion 246 b and aspring arm portion 246 c. The coil portion 246 a surrounds a supportprojection 14 h (see FIG. 34) formed on a side of the mirror box 14, thespring arm portion 246 b is engaged with a spring hook 14 i formed on aside of the mirror box 14, and the spring arm portion 246 c is engagedwith the base of the shock-absorbing pin 245 a of the mirror-upshock-absorbing slider 245. The mirror-up shock-absorbing spring 246biases the mirror-up shock-absorbing slider 245 downward with respect toFIGS. 34 through 40. This biasing direction of the mirror-upshock-absorbing slider 245 by the mirror-up shock-absorbing spring 246is a direction which brings the shock-absorbing pin 245 a close to (tobring into contact with) the shock-absorbing contact portion 16 c of themirror seat 16, and the engagement of the mirror-up shock-absorbingslider 245 with the lower end of the support guide hole 243 e preventsthe mirror-up shock-absorbing slider 245 from moving in the biasingdirection of the mirror-up shock-absorbing spring 246. Morespecifically, the mirror-up shock-absorbing slider 245 is prevented frommoving further downward (moving in the biasing direction of themirror-up shock-absorbing spring 246) by engagement with the lower endof the support guide hole 243 e when the release lever 243 is in theaforementioned rotational limit position. This movement limit of themirror-up shock-absorbing slider 245 in the downward direction will behereinafter referred to as “shock-absorbing standby position.”

The lock lever 247 is pivoted on a shaft 247 x which projects from aside of the mirror box 14 and is substantially parallel to the shaft 41x of the mirror-down shock-absorbing lever 241. The lock lever 247 isprovided with a linking arm (radial projection) 247 a which projects ina radial outward direction of the shaft 247 x, and the linking arm 247 ais held by an arm holding portion 243 g formed on the release lever 243.The arm holding portion 243 g includes a pair of projections that arespaced from each other in the advancing/retracting direction of therelease lever 243 (the vertical direction with respect to FIGS. 35through 40). The linking arm 247 a is inserted between theaforementioned pair of projections, so that upward and downwardmovements of the release lever 243 cause the lock lever 247 to rotateforward and reverse. The lock lever 247 is provided at the end of thelinking arm 247 a with a holding recess 247 b which is recessed and hasa shape corresponding to the shape of an outer peripheral surface of thelock pin 245 b of the mirror-up shock-absorbing slider 245. When therelease lever 243 is in the aforementioned rotational limit position,the lock lever 247 is held in an unlock position (shown in FIGS. 35through 37 and 40) in which the linking arm 247 a (the holding recess247 b) is retracted from the path of movement of the lock pin 245 b.When the release lever 243 is moved upward from the rotational limitposition, this upward movement of the release lever 243 causes the locklever 247 to rotate to a lock position (shown in FIGS. 38 and 39) inwhich the linking arm 247 a (the holding recess 247 b) is positioned inthe path of movement of the lock pin 245 b. The distance between thepair of projections that comprise the arm holding portion 243 g isslightly greater than the width of the linking arm 247 a so that the armholding portion 243 g does not interfere with smooth rotation of thelock lever 247.

Operations of the mirror shock-absorbing mechanism 40E will behereinafter discussed with reference to FIGS. 35 through 40. FIG. 35shows a state where the movable mirror 15 is in the mirror-downposition. The release lever 243 is held in the rotational limit positionby the biasing force of the release spring 244, and prevents themirror-down shock-absorbing lever 241 from rotating in the biasingdirection of the mirror-down shock-absorbing spring 242 (i.e., in theclockwise direction with respect to FIGS. 35 through 40) by bringing therotation-restricting arm 243 c into contact with the rotationallyrestricted surface 41 b. At this stage, the mirror-down shock-absorbinglever 241 is in the overrun position, in which the shock-absorbing pin41 a is disengaged from the shock-absorbing contact portion 16 c of themirror seat 16 in a mirror-down direction (counterclockwise directionwith respect to FIG. 35). The mirror-up shock-absorbing slider 245 isheld in the shock-absorbing standby position, in which a lower endsurface of the mirror-up shock-absorbing slider 245 is engaged with thelower end of the support guide hole 243 e, by the biasing force of themirror-up shock-absorbing spring 246. In addition, the lock lever 247 isheld in the unlock position, in which the holding recess 247 b isretracted from the path of movement of the lock pin 245 b.

When the movable mirror 15 is rotated from the mirror-down positiontoward the mirror-up position, this rotation of the movable mirror 15causes an upper surface of the shock-absorbing contact portion 16 c ofthe mirror seat 16 to come into contact with the shock-absorbing pin 245a of the mirror-up shock-absorbing slider 245 as shown in FIG. 36. Fromthis state, a further rotation of the movable mirror 15 toward themirror-up position causes the shock-absorbing contact portion 16 c ofthe mirror seat 16 to lift the shock-absorbing pin 245 a to press andmove the mirror-up shock-absorbing slider 245 upward from theshock-absorbing standby position against the biasing force of themirror-up shock-absorbing spring 246. At an initial stage of this upwardmovement of the mirror-up shock-absorbing slider 245, the mirror-upshock-absorbing slider 245 slidingly moves in the support guide hole 243e while the release lever 243 is not moved. Namely, the mirror-upshock-absorbing slider 245 moves solely (independently) while therelease lever 243 remains in the rotational limit position, in which therelease lever 243 prevents the mirror-down shock-absorbing lever 241from rotating. Subsequently, upon the mirror shock-absorbing mechanism40E entering the state shown in FIG. 37, in which the upper end surfaceof the mirror-up shock-absorbing slider 245 comes in contact with theupper end of the support guide hole 243 e, the pressing and moving forceby the movable mirror 15 also starts acting on the release lever 243,which causes the release lever 243 and the mirror-up shock-absorbingslider 245 to integrally move upward. At this stage, in addition to thebiasing force of the mirror-up shock-absorbing spring 246, the biasingforce of the release spring 244 also acts on the movable mirror 15, sothat the movable mirror 15 rotates toward the mirror-up position whilereceiving loads from the release spring 244 and the mirror-upshock-absorbing spring 246. When the release lever 243 moves upward fromthe rotational limit position, this upward movement of the release lever243 causes the rotation-restricting arm 243 c of the release lever 243to retract upward from the path of rotational movement of therotationally restricted surface 41 b of the mirror-down shock-absorbinglever 241. This releases the prevention of rotation of the mirror-downshock-absorbing lever 241, so that the mirror-down shock-absorbing lever241 rotates to the shock-absorbing standby position, in which themirror-down shock-absorbing lever 241 contacts the rotational limitprojection 214 c by the biasing force of the mirror-down shock-absorbingspring 242, as shown in FIG. 38. When the mirror-down shock-absorbinglever 241 is in the shock-absorbing standby position, theshock-absorbing pin 41 a is positioned above the mirror-down positiondefining pin 20, namely, at a position advanced in a mirror-up direction(clockwise direction with respect to FIG. 38) of the movable mirror 15.

FIG. 38 shows a state where the release lever 243 and the mirror-upshock-absorbing slider 245 have been lifted upward by the movable mirror15 rotated to the mirror-up position. As described above, from the stateshown in FIG. 36, in which the shock-absorbing contact portion 16 c ofthe mirror seat 16 commences to contact the shock-absorbing pin 245 a,to the state shown in FIG. 37, in which the mirror-up shock-absorbingslider 245 comes in contact with the upper end of the support guide hole243 e, the movable mirror 15 presses and moves the mirror-upshock-absorbing slider 245 against the biasing force of the mirror-upshock-absorbing spring 246. From the state shown in FIG. 37 until themirror-up completion state shown in FIG. 38, the movable mirror 15presses and integrally moves the release lever 243 and the mirror-upshock-absorbing slider 245 against the biasing forces of the releasespring 244 and the mirror-up shock-absorbing spring 246. Namely, as themovable mirror 15 approaches the mirror-up position, the spring loads ofthe release spring 244 and the mirror-up shock-absorbing spring 246 areexerted on rotation of the movable mirror 15, and the movable mirror 15reaches the mirror-up position while being shock-absorbed (cushioned) bythe mirror-up shock-absorbing slider 245, the mirror-up shock-absorbingspring 246, the release lever 243 and the release spring 244. Thissuppresses the occurrence of bouncing (vibrations) of the movable mirror15 when the movable mirror 15 rotates from the mirror-down position tothe mirror-up position. When the movable mirror 15 is in the mirror-upposition, the engagement of an upper surface of the mirror seat 16 withthe upper stopper 21 prevents the movable mirror 15 from moving furtherupward (see FIG. 1). Additionally, in the state shown in FIG. 38, themirror-up shock-absorbing slider 245 is prevented from moving furtherupward by engagement of the lower end of the guide hole 245 c with theguide pin 14 e. The movable mirror 15 comes into contact with the upperstopper 21 before the mirror-up shock-absorbing slider 245 reaches thisupper movement limit. Namely, similar to the mirror-down shock-absorbinglever 241, ahead of the aforementioned shock-absorbing moving range (inwhich the shock-absorbing pin 245 a is pressed by the shock-absorbingcontact portion 16 c of the movable mirror 15 (the mirror seat 16)), themirror-up shock-absorbing slider 245 also has an overrun range in whichthe shock-absorbing pin 245 a is disengaged from the shock-absorbingcontact portion 16 c of the movable mirror 15 suspended in the mirror-upposition by the upper stopper 21. However, the overrun range of themirror-up shock-absorbing slider 245 is set to be narrower than theoverrun range of the mirror-up shock-absorbing lever 241.

As shown in FIG. 38, when the release lever 243 is moved upward from therotational limit position in response to rotation of the movable mirror15 toward the mirror-up position, this upward movement of the releaselever 243 causes the arm holding portion 243 g of the release lever 243to lift the linking arm 247 a, which causes the lock lever 247 to rotatefrom the unlock position to the lock position. Thereupon, the linkingarm 274 a of the lock lever 247 advances to a position immediately belowthe lock pin 245 b of the mirror-up shock-absorbing slider 245 that hasbeen moved upward together with the release lever 243, so that the lockpin 245 b is engaged in and supported by the holding recess 247 b. Atthis stage, the rotation allowance surface 41 c of the mirror-upshock-absorbing lever 241 rotated to the shock-absorbing standbyposition is positioned below the rotation-restricting arm 243 c of therelease lever 243, and the release lever 243 is prevented from movingfurther downward by engagement of the rotation-restricting arm 243 cwith the rotation allowance surface 41 c, as shown in FIG. 39. In otherwords, the range of movement of the release lever 243 (at this stage) inthe vertical direction is limited only to the range of the clearancebetween the rotation-restricting arm 243 c and the rotation allowancesurface 41 c. In this limited range of movement of the release lever243, the linking arm 247 a (the holding recess 247 b) of the lock lever247 does not move off the path of movement of the lock pin 245 b andtherefore the lock lever 247 remains held in the lock position.Accordingly, even if the mirror-up shock-absorbing slider 245 attemptsto move downward, i.e., in the biasing direction of the mirror-upshock-absorbing spring 246, the engagement between the lock pin 245 band the holding recess 247 b prevents the mirror-up shock-absorbingslider 245 from moving downward. Namely, as the movable mirror 15approaches the mirror-up position, the range of movement of the releaselever 243 and the range of movement of the mirror-up shock-absorbingslider 245 are each limited by the mirror-up shock-absorbing lever 241and the lock lever 247, so that the repulsive motion of theshock-absorbing pin 245 a when bouncing of the movable mirror 15 isabsorbed can be reduced to a minimal amount. As a result, bouncing ofthe movable mirror 15 which is applied via the shock-absorbing pin 245 ais reduced within the range between the position of the movable mirror15 shown by solid lines and the position of the movable mirror 15 shownby two-dot chain lines in FIG. 39.

When the movable mirror 15 rotates from the mirror-up position to themirror-down position, the biasing forces of the release spring 244 andthe mirror-up shock-absorbing spring 246 urge the release lever 243 andthe mirror-up shock-absorbing slider 245 to move downward because thelifted state of the release lever 243 and the mirror-up shock-absorbingslider 245 by the shock-absorbing contact portion 16 c of the mirrorseat 16 of the movable mirror 15 rotated to the mirror-up position iscancelled. A further downward movement of the release lever 243 isstopped partway down by the engagement of the lower end of therotation-restricting arm 243 c with the rotation allowance surface 41 cof the mirror-down shock-absorbing lever 241 as shown in FIG. 39. Whenthe release lever 243 is in this position, the lock lever 247 is held inthe lock position as described above, so that the mirror-upshock-absorbing slider 245 is prevented from moving downward by theengagement of the holding recess 247 b with the lock pin 245 b.Subsequently, as the movable mirror 15 approaches the mirror-downposition, the shock-absorbing contact portion 16 c of the mirror seat 16comes into contact with the shock-absorbing pin 41 a of the mirror-downshock-absorbing lever 241 before the stopper 16 a of the mirror seat 16comes into contact with the mirror-down position defining pin 20. Atthis stage, the mirror-down shock-absorbing lever 241 is held in theshock-absorbing standby position by the biasing force of the mirror-downshock-absorbing spring 242, and during the rotation of the movablemirror 15 to the mirror-down position, shown in FIG. 40, theshock-absorbing contact portion 16 c of the mirror seat 16 depresses theshock-absorbing pin 41 a of the mirror-down shock-absorbing lever 241 torotate the mirror-down shock-absorbing lever 241 counterclockwise fromthe shock-absorbing standby position, shown in FIGS. 38 and 39, againstthe biasing force of the mirror-down shock-absorbing spring 242. At thisstage, the mirror-down shock-absorbing lever 241 can rotate with therotation allowance surface 41 c in sliding contact with the end of therotation-restricting arm 243 c without being restricted by the releaselever 243. Accordingly, during rotation of mirror-down shock-absorbinglever 241 in the shock-absorbing moving range that starts from theshock-absorbing standby position, the spring load of the mirror-downshock-absorbing spring 242 is exerted on rotation of the movable mirror15, and the movable mirror 15 reaches the mirror-down position whilebeing shock-absorbed (cushioned) by the mirror-down shock-absorbinglever 241 and the mirror-down shock-absorbing spring 242.

FIG. 40 shows a state immediately after the movable mirror 15 is rotatedto the mirror-down position. Similar to the state shown in FIG. 35, thestopper 16 a of the mirror seat 16 comes into contact with themirror-down position defining pin 20 to thereby prevent the movablemirror 15 from rotating in the mirror-down direction (counterclockwisedirection with respect to FIG. 40). As a result of the mirror-downshock-absorbing lever 241 having been pressed and rotated from theshock-absorbing standby position, the prevention of movement of therelease lever 243 by engagement of the rotation allowance surface 41 cwith the rotation-restricting arm 243 c is released, and the releaselever 243 has been moved down to the shock-absorbing standby position bythe biasing force of the release spring 244 as described above. Thiscauses the rotation-restricting arm 243 c to move onto the path ofrotational movement of the rotationally restricted surface 41 b to againprevent the mirror-down shock-absorbing lever 241 from rotating towardthe shock-absorbing standby position (clockwise direction with respectto FIG. 40). Similar to the mirror-down shock-absorbing lever 41 of thefirst embodiment of the mirror shock-absorbing mechanism, when themovable mirror 15 rotates to the mirror-down position, the mirror-downshock-absorbing lever 241 rotates by inertia to the position shown inFIG. 40, and subsequently returns to the position shown in FIG. 35 (intothe overrun range in which the shock-absorbing pin 41 a is disengagedfrom the shock-absorbing contact portion 16 c of the mirror seat 16 inthe mirror-down state), in which the rotationally restricted surface 41b is made to contact the rotation-restricting arm 243 c of the releaselever 243.

Additionally, the movement of the release lever 243 to the rotationallimit position causes the arm holding portion 243 g to depress thelinking arm 247 a, which causes the lock lever 247 to rotate from thelock position to the unlock position. Thereupon, the linking arm 274 aof the lock lever 247 retracts from the path of movement of the lock pin245 b, which causes the holding recess 247 b and the lock pin 245 b tobe disengaged from each other to thereby allow the mirror-upshock-absorbing slider 245 to move downward in the support guide hole243 e. Consequently, the biasing force of the mirror-up shock-absorbingspring 246 causes the mirror-up shock-absorbing slider 245 to move downto the shock-absorbing standby position, which corresponds to the limitof downward movement of the mirror-up shock-absorbing slider 245.

As described above, in the mirror shock-absorbing mechanism. 40E,bouncing of the movable mirror 15 is suppressed by making theshock-absorbing pin 41 a of the mirror-down shock-absorbing lever 241and the shock-absorbing pin 245 a of the mirror-up shock-absorbingslider 245 into contact with the mirror seat 16 when the movable mirror15 rotates between the mirror-down position and the mirror-up position,respectively. Additionally, the mirror shock-absorbing mechanism 40E isstructured such that firstly the mirror-up shock-absorbing slider 245 issolely pressed and moved and subsequently the release lever 243 ispressed and moved together with the mirror-up shock-absorbing slider 245when shock of the movable mirror 15 which is caused upon the movablemirror 15 rotating from the mirror-down position to the mirror-upposition is absorbed. Although a load starts acting on the movablemirror 15 from the moment in time (shown in FIG. 36) at which theshock-absorbing contact portion 16 c of the mirror seat 16 commences topress the shock-absorbing pin 245 a of the mirror-up shock-absorbingslider 245, the release lever 243 is held at a stationary (constant)position during the time until the mirror-up shock-absorbing slider 245commences to move integrally with the release lever 243 (i.e., until themirror shock-absorbing mechanism 40E enters the state shown in FIG. 37).Accordingly, the space for movement of the release lever 243, whichsupports the mirror-up shock-absorbing slider 245, is reduced to aminimum while a wide range of movement of the mirror-up shock-absorbingslider 245, which directly comes in contact with the shock-absorbingcontact portion 16 c of the mirror seat 16, is secured, and hence anexcellent capability of absorbing shock of the movable mirror 15 can beobtained, even though the mirror shock-absorbing mechanism 40E iscompact in structure.

Additionally, in the mirror shock-absorbing mechanism 40E, the mirror-upshock-absorbing slider 245 and the release lever 243 are separatelybiased by the mirror-up shock-absorbing spring 246 and the releasespring 244, respectively; in addition, when the movable mirror 15rotates to the mirror-up position, first the spring load of themirror-up shock-absorbing spring 246 is exerted on the movable mirror 15and subsequently the spring load of the release spring 244 is exerted onthe movable mirror 15 in addition to the spring load of the mirror-upshock-absorbing spring 246. Therefore, at an initial stage of the mirrorshock-absorbing operation, the load on the movable mirror 15 is small,thus not reducing the rotating speed of the movable mirror 15; however,as the movable mirror 15 approaches the mirror-up position, the load onthe movable mirror 15 is increased to reliably reduce bouncing of themovable mirror 15. Moreover, by adjusting the biasing forces of themirror-up shock-absorbing spring 246 and the release spring 244, thedegree of shock-absorbing can be easily set.

Additionally, in a state where the movable mirror 15 is in the mirror-upposition, the mirror-up shock-absorbing slider 245 is prevented frommoving downward by the lock lever 247 while the release lever 243 isprevented from moving downward by the mirror-down shock-absorbing lever241. As a result, the range of movement of the shock-absorbing pin 245 athat contacts the shock-absorbing contact portion 16 c of the mirrorseat 16 is limited, which makes it possible to minimize bouncing of themovable mirror 15. Additionally, since the mirror-down shock-absorbinglever 241 that limits the range of downward movement of the releaselever 243 is a member which absorbs shock of the movable mirror 15 whenthe movable mirror 15 rotates from the mirror-up position to themirror-down position, the number of elements of the mirrorshock-absorbing mechanism 40E is smaller than that in the case where themirror shock-absorbing mechanism is provided with an additional memberwhich limits the range of movement the release lever 243, hence, themirror shock-absorbing mechanism 40E is simple in structure.Additionally, the lock lever 247 that limits the range of downwardmovement of the mirror-up shock-absorbing slider 245 is a member whichis rotated between the lock position and the unlock position inaccordance with movement of the release lever 243 that supports themirror-up shock-absorbing slider 245, and accordingly, the lock lever247 can be operated via a simple structure.

In addition, similar to each of the first through fourth embodiments ofthe mirror shock-absorbing mechanisms, the mirror-down shock-absorbinglever 241 is prevented from rotating in the biasing direction of themirror-down shock-absorbing spring 242 by engagement of the rotationallyrestricted surface 41 b of the mirror-down shock-absorbing lever 241with the rotation-restricting arm 243 c of the release lever 243 whenthe movable mirror 15 rotates from the mirror-up position to themirror-down position, contrary to when the movable mirror 15 rotatesfrom the mirror-down position to the mirror-up position, so that noinfluence is exerted on the positioning of the movable mirror 15 that isdefined by the mirror-down position defining pin 20. Namely, therelationship between the mirror-down shock-absorbing lever 241 and therelease lever 243 is such that the positions thereof are mutuallyrestricted when the movable mirror 15 is rotated to the mirror-downposition and when the movable mirror 15 is rotated to the mirror-upposition, which achieves a simplification of the structure.

Additionally, the biasing forces of the mirror-down shock-absorbingspring 242, the release spring 244 and the mirror-up shock-absorbingspring 246 are used not only to absorb shock of the movable mirror 15but also to limit movements of the mirror-up shock-absorbing slider 245and the release lever 243 in a state where the movable mirror 15 is inthe mirror-up position and to hold the mirror-down shock-absorbing lever241 in a state where the movable mirror 15 is in the mirror-downposition, which also contributes to the simplification of the structure.

As described above, the above illustrated fifth embodiment of the mirrorshock-absorbing mechanism 40E is constructed such that shock-absorbingis performed by the mirror-up shock-absorbing slider 245 and the releaselever 243, which serve as members which absorb shock of the movablemirror 15 in two stages when the movable mirror 15 rotates from themirror-down position (viewfinder light-guiding position) to themirror-up position (retracted position), and that the suppression ofbouncing of the mirror-up shock-absorbing slider 245 and the releaselever 243 is performed using the mirror-down shock-absorbing lever 241and the lock lever 247 that serve as a shock absorber for absorbingshock of the movable mirror 15 when the movable mirror 15 rotates fromthe mirror-up position (retracted position) to the mirror-down position(viewfinder light-guiding position). In contrast, the above descriptionof the fifth embodiment of the mirror shock-absorbing mechanism 40E isread with the terms “the mirror-up position” and “the mirror-downposition” reversed, the present invention is also applicable to obtainsimilar effects when the movable mirror 15 rotates from the mirror-upposition (retracted position) to the mirror-down position (viewfinderlight-guiding position).

A sixth embodiment of the mirror shock-absorbing mechanism 40F will behereinafter discussed with reference to FIGS. 41 through 51. The mirrorshock-absorbing mechanism 40F is provided with a mirror-downshock-absorbing lever (first shock-absorbing member) 341, a mirror-downshock-absorbing spring (first biaser) 342, a mirror-up shock-absorbinglever (second shock-absorbing member) 343 and a mirror-upshock-absorbing spring (second biaser) 344. The mirror-downshock-absorbing lever 341, the mirror-down shock-absorbing spring 342,the mirror-up shock-absorbing lever 343 and the mirror-upshock-absorbing spring 344 are held so as not to come off the mirror box14 by a retaining plate 348 (see FIG. 41) fixed to a side of the mirrorbox 14. The mirror-down shock-absorbing lever 341, the mirror-downshock-absorbing spring 342, the mirror-up shock-absorbing lever 343 andthe mirror-up shock-absorbing spring 344 correspond to the mirror-downshock-absorbing lever 141, the mirror-down shock-absorbing spring 142,the mirror-up shock-absorbing lever 143 and the mirror-upshock-absorbing spring 144 of the third embodiment of the mirrorshock-absorbing mechanism 40C, respectively, and elements of the sixthembodiment of the mirror shock-absorbing mechanism 40F which are thesame as those of the third embodiment of the mirror shock-absorbingmechanism 40C are designated by the same reference numerals and thedetailed description of the same elements will be omitted.

The mirror-down shock-absorbing lever 341 is provided with a control arm(first movement control member) 41 g, which projects in a directionperpendicular to the shaft 41 x of the mirror-down shock-absorbing lever341, at an outer radial position away from the shaft 41 x. Arotationally restricted surface 41 h is formed on one side of thecontrol arm 41 g, and an inclined cam surface (auxiliary pressingmember/first sliding contact surface) 41 i is formed on aside of thecontrol arm 41 g that is adjacent to the rotationally restricted surface41 h. The rotationally restricted surface 41 h is a surface that extendsin a radial direction that is centered approximately at the axis of theshaft 41 x. The inclined cam surface 41 i is a surface which is inclinedwith respect to the rotational direction of the mirror-downshock-absorbing lever 341. More specifically, the inclined cam surface41 i is a surface which inclines in a manner so as to gradually increasethe distance thereof from the shaft 41 x at a point increasingly distantfrom the boundary position between the rotationally restricted surface41 h and the inclined cam surface 41 i. A downward-restrictingprotrusion 41 j is formed at the end (tip) of the control arm 41 g in acontinuous manner with the inclined cam surface 41 i.

The mirror-down shock-absorbing spring 342 is a torsion spring similarto the mirror-down shock-absorbing springs 42, 142 and 242 of each ofthe first through fifth embodiments of the mirror shock-absorbingmechanisms. The mirror-down shock-absorbing spring 342 biases themirror-down shock-absorbing lever 341 in a direction to rotate themirror-down shock-absorbing lever 341 toward a shock-absorbing standbyposition, in which the mirror-down shock-absorbing lever 341 comes incontact with a rotational limit projection 314 c which projects from aside of the mirror box 14.

A hook-shaped thick end-portion (second movement control member) 43 i,which is bent downwardly, is formed at an end part of a side arm 43 hthat is provided on the mirror-up shock-absorbing lever 343. Arotational restricting surface 43 j, an inclined cam surface (auxiliarypressing member/second sliding contact surface) 43 k, and adownward-movement restricting surface 43 m are formed on the thickend-portion 43 i. The rotational restricting surface 43 j is formed as aflat surface (plane) that is substantially parallel to the movingdirection of the mirror-up shock-absorbing lever 343. An inclined camsurface 43 k is formed as a surface that is inclined to the linearmovement direction of the mirror-up shock-absorbing lever 343. Morespecifically, the inclined cam surface 43 k is a surface which inclinesin a manner so as to gradually increase the distance thereof from thebody of the mirror-up shock-absorbing lever 343 (so as to approach theend of the side arm 43 h) at a point increasingly distant from theboundary position between the rotational restricting surface 43 j andthe inclined cam surface 43 k in a downward direction. Thedownward-movement restricting surface 43 m is a surface which facesdownwardly, formed in a continuous manner from the inclined cam surface43 k, and defines a flat surface which is substantially orthogonal tothe movement direction of the mirror-up shock-absorbing lever 343. Therotational restricting surface 43 j, the inclined cam surface 43 k andthe downward-movement restricting surface 43 m are positioned in(intersect) a common plane defined by the control arm 41 g of themirror-down shock-absorbing lever 341, so that it is possible for thecontrol arm 41 g and the thick end-portion 43 i to mutually contact eachother in accordance with the relative positional relationship of themirror-down shock-absorbing lever 341 and the mirror-up shock-absorbinglever 343.

The mirror-up shock-absorbing spring 344 is an extension spring whichbiases the movement of the mirror-up shock-absorbing lever 343 towardthe downward shock-absorbing standby position. At the shock-absorbingstandby position of the mirror-up shock-absorbing lever 343, the thickend-portion 43 i of the side arm 43 h enters into the rotational path ofthe control arm 41 g, defined about the shaft 41 x of the mirror-downshock-absorbing lever 341, so that the rotation of the mirror-downshock-absorbing lever 341 toward the biasing direction of themirror-down shock-absorbing spring 342 is restricted due to therotational restricting surface 43 j abutting against the rotationallyrestricted surface 41 h in order to hold the mirror-down shock-absorbinglever 341 within the overrun range (FIGS. 46 and 47).

Whereas, in a state in which the thick end-portion 43 i of the side arm43 h is released from the rotational path of the control arm 41 g (seeFIG. 49), the holding of the mirror-down shock-absorbing lever 341 inthe overrun range is released, so that the mirror-down shock-absorbinglever 341 can rotate toward the biasing direction (shock-absorbingstandby position) of the mirror-down shock-absorbing spring 342. Whenthe mirror-down shock-absorbing lever 341 is in the shock-absorbingstandby position, the control arm 41 g enters into the rotational pathof the thick end-portion 43 i of the side arm 43 h, so that movement ofthe mirror-up shock-absorbing lever 343 toward the biasing direction(shock-absorbing standby position) of the mirror-up shock-absorbingspring 344 is restricted by the downward-restricting protrusion 41 jabutting against the downward-movement restricting surface 43 m (seeFIG. 50).

Operations of the mirror shock-absorbing mechanism 40F will behereinafter discussed with reference to FIGS. 46 through 51. FIG. 46shows a state where the movable mirror is in the mirror-down position.The mirror-up shock-absorbing lever 343 is held in the shock-absorbingstandby position by the biasing force of the mirror-up shock-absorbingspring 344 and prevents the mirror-down shock-absorbing lever 341 fromrotating in the biasing direction of the mirror-down shock-absorbingspring 342 (i.e., in the clockwise direction with respect to FIG. 46) bybringing the side arm 43 h of the rotational restricting surface 43 jinto contact with the rotationally restricted surface 41 h of thecontrol arm 41 g. At this stage, the mirror-down shock-absorbing lever341 is held in the overrun position, in which the shock-absorbing pin 41a is disengaged from the shock-absorbing contact portion 16 c of themirror seat 16 in the mirror-down direction (counterclockwise directionwith respect to FIG. 46).

When the movable mirror 15 is rotated from the mirror-down positiontoward the mirror-up position to thereby bring an upper surface of theshock-absorbing contact portion 16 c of the mirror seat 16 into contactwith the shock-absorbing pin 43 c of the mirror-up shock-absorbing lever343 as shown in FIG. 47, the mirror-up shock-absorbing lever 343 ispressed and moved upward from the shock-absorbing standby positionagainst the biasing force of the mirror-up shock-absorbing spring 344.

Upon the mirror-up shock-absorbing lever 343 being pressed and movedupward from the shock-absorbing standby position, the rotationalrestricting surface 43 j of the thick end-portion 43 i (of the side arm43 h) retracts upward from the opposing position of the control arm 41 gof the mirror-down shock-absorbing lever 341. Since the inclined camsurface 43 k, which is continuously formed with the rotationalrestricting surface 43 j, is a surface which is inclined in a directionaway from the control arm 41 g at a point increasingly downward, themirror-down shock-absorbing lever 341 which is released from therotational restriction from the rotational restricting surface 43 jslightly rotates in the clockwise direction while the control arm 41 gslides against the inclined cam surface 43 k by the biasing force of themirror-down shock-absorbing spring 342. Consequently, as shown in FIG.48, the inclined cam surface 41 i of the mirror-down shock-absorbinglever 341 abuts against the thick end-portion 43 i (the boundaryposition between the inclined cam surface 43 k and the downward-movementrestricting surface 43 m) of the mirror-up shock-absorbing lever 343. Atthis stage, the movable mirror 15 has not yet reached the mirror-upposition.

Upon reaching the state shown in FIG. 48, the upward pressing force ofthe control arm 41 g of the mirror-down shock-absorbing lever 341 thatrotates to the shock-absorbing standby position by the biasing force ofthe mirror-down shock-absorbing spring 342 also acts on the mirror-upshock-absorbing lever 343 together with the upward pressing force of theshock-absorbing contact portion 16 c of the mirror seat 16.Specifically, upon the mirror-down shock-absorbing lever 341 rotating inthe clockwise direction by the biasing force of the mirror-downshock-absorbing spring 342, a component of force occurs that acts on themirror-up shock-absorbing lever 343 to push the mirror-upshock-absorbing lever 343 upward in accordance with the inclinationshape of the inclined cam surface 41 i while the inclined cam surface 41i slides against the thick end-portion 43 i of the side arm 43 h. Themovement resistance of the mirror-up shock-absorbing spring 344 againstthe mirror-up shock-absorbing lever 343 gradually increases from whenthe shock-absorbing contact portion 16 c and the shock-absorbing pin 43c start to abut each other, as shown in FIG. 47, until reaching thestate shown in FIG. 48. However, since the mirror-down shock-absorbinglever 341 supplementally presses the mirror-up shock-absorbing lever343, the load of the mirror-up shock-absorbing lever 343 against themovable mirror does not become excessive, so that the mirror-upshock-absorbing lever 343 can reliably and securely be moved to theupper position, which corresponds to the mirror-up position of themovable mirror 15. In other words, the mirror-up shock-absorbing lever343 is not hindered from reaching the mirror-up position of the movablemirror 15. Note that while the mirror-down shock-absorbing lever 341presses against the mirror-up shock-absorbing lever 343 using theinclined cam surface 41 i, since a pressing component force also acts onthe mirror-up shock-absorbing lever 343 in a direction intersecting thelinear movement direction of the guiding action of the guide hole 43 fand the guide pins 14 d and 14 e, any backlash that would otherwiseoccur between the guide hole 43 f and the guide pins 14 d and 14 e isabsorbed, so that an effect is also obtained in which the mirror-upshock-absorbing lever 343 can smoothly move without play.

Thereafter, upon the mirror-up shock-absorbing lever 343 being movedupward until the entire side arm 43 h is totally removed upwardly fromthe rotational path of the control arm 41 g, the rotational restrictionagainst the mirror-down shock-absorbing lever 341 is completelyreleased, so that the mirror-down shock-absorbing lever 341 rotatesuntil the shock-absorbing standby position, at which the mirror-downshock-absorbing lever 341 abuts against the rotational limit projection314 c, by the biasing force of the mirror-down shock-absorbing spring342 (see FIG. 49).

As shown in FIG. 49, when the mirror-down shock-absorbing lever 341 isrotated to the shock-absorbing standby position, thedownward-restricting protrusion 41 j is positioned immediately below thedownward-movement restricting surface 43 m of the mirror-upshock-absorbing lever 343. FIG. 49 shows a state where the mirror-upshock-absorbing lever 343 has been moved up by the movable mirror 15rotated to the mirror-up position to thereby create a slight gap betweenthe end (tip) of the downward-restricting protrusion 41 j and thedownward-movement restricting surface 43 m. From this state, a downwardmovement of the mirror-up shock-absorbing lever 343 causes thedownward-movement restricting surface 43 m to come into contact with theend (tip) of the downward-restricting protrusion 41 j as shown in FIG.50, and engagement of the downward-movement restricting surface 43 mwith the downward-restricting protrusion 41 j prevents the mirror-upshock-absorbing lever 343 from moving further downward.

As described above, when the movable mirror 15 rotates from themirror-down position to the mirror-up position, the spring load of themirror-up shock-absorbing spring 344 is exerted on rotation of themovable mirror 15 to absorb shock of the movable mirror 15 by engagementof the shock-absorbing contact portion 16 c of the mirror sheet 16 withthe shock-absorbing pin 43 c of the mirror-up shock-absorbing lever 343.Additionally, the range of movement (the amount of downward movement) ofthe mirror-up shock-absorbing lever 343 in a state where the movablemirror 15 has reached the mirror-up position is limited to an extremelysmall range by the engagement between the downward-movement restrictingsurface 43 m and the downward-restricting protrusion 41 j of themirror-down shock-absorbing lever 341. This reduces the degree ofrebounding movement of the mirror-up shock-absorbing lever 343, shortensthe duration of bouncing (vibration) of the movable mirror 15 andreduces the number of bounces thereof when the movable mirror 15 rotatesto the up position. Namely, the shock-absorbing capability for themovable mirror is enhanced. Additionally, since the mirror-downshock-absorbing lever 341 supplementally presses the mirror-upshock-absorbing lever 343 using the inclined cam surface 41 i, themirror-up shock-absorbing lever 343 can reliably and securely be movedto the upper position, which corresponds to the mirror-up position ofthe movable mirror 15.

In a reverse operation to the above described mirror-up operation, asthe movable mirror 15 approaches the mirror-down position while rotatingfrom the mirror-up position, the shock-absorbing contact portion 16 c ofthe mirror sheet 16 comes into contact with the shock-absorbing pin 41 aof the mirror-down shock-absorbing lever 341 before the stopper 16 a ofthe mirror sheet 16 comes into contact with the down-position definingpin 20, as shown in FIG. 50. At this stage, the mirror-downshock-absorbing lever 341 is held in the shock-absorbing standbyposition by the biasing force of the mirror-down shock-absorbing spring342, and movement of the mirror-up shock-absorbing lever 343 toward thebiasing direction (shock-absorbing standby position) of the mirror-upshock-absorbing spring 344 is restricted by the downward-restrictingprotrusion 41 j abutting against the downward-movement restrictingsurface 43 m.

During the rotation of the movable mirror 15 from the position shown inFIG. 50 until the mirror-down position shown in FIG. 51, theshock-absorbing contact portion 16 c of the mirror seat 16 pushes theshock-absorbing pin 41 a downward, rotating the mirror-downshock-absorbing lever 341 in an anti-clockwise direction from theshock-absorbing standby position, shown in FIG. 50, against the biasingforce of the mirror-down shock-absorbing spring 342. FIG. 51 shows theinstance when the movable mirror 15 has reached the mirror-downposition, at which the stopper 16 a abuts the mirror-down register pin20. During the mirror-down operation of the movable mirror 15, theposition of the movable mirror 15 shown in FIG. 50 until the positionthereof in FIG. 51 define the range (shock-absorbing moving range) inwhich a shock-absorbing effect can be achieved by the mirror-downshock-absorbing lever 341. The mirror-down shock-absorbing lever 341 isrotated by the inertial force from the position shown in FIG. 51 to theabove-mentioned overrun range advanced further in the anti-clockwisedirection. In the state shown in FIG. 51, the downward-restrictingprotrusion 41 j of the mirror-down shock-absorbing lever 341 is alreadyremoved from the lower position of the downward-movement restrictingsurface 43 m of the side arm 43 h, so that the mirror-up shock-absorbinglever 343, which has been released from restriction of downward movementthereof, is moved toward the shock-absorbing standby position by thebiasing force of the mirror-up shock-absorbing spring 344, and theinclined cam surface 43 k abuts against the control arm 41 g (theboundary position between the rotationally restricted surface 41 h andthe inclined cam surface 41 i). Thereafter, the downward pressing forceof the side arm 43 h (thick end-portion 43 i) of the mirror-upshock-absorbing lever 343, which moves toward the shock-absorbingstandby position by the biasing force of the mirror-up shock-absorbingspring 344 together with the inertial moving force of the mirror-upshock-absorbing lever 343, also acts on the mirror-down shock-absorbinglever 341. Specifically, when the mirror-up shock-absorbing lever 343moves down from the position thereof shown in FIG. 51 by the biasingforce of the mirror-up shock-absorbing spring 344, a component forceoccurs which rotates the mirror-down shock-absorbing lever 341 in theanti-clockwise direction in accordance with the inclined shape of theinclined cam surface 43 k while the inclined cam surface 43 k slidesagainst the control arm 41 g. The movement resistance of thedownward-absorbing spring 342 against the mirror-down shock-absorbinglever 341 gradually increases from when the shock-absorbing contactportion 16 c and the shock-absorbing pin 41 a start to abut each other,as shown in FIG. 50, until reaching the state shown in FIG. 51. However,since the mirror-up shock-absorbing lever 343 supplementally presses themirror-down shock-absorbing lever 341, the mirror-down shock-absorbinglever 341 can reliably and securely be moved to the lower position whichcorresponds to the mirror-down position of the movable mirror 15.

As described above, in the mirror shock absorbing mechanism 40F, sincethe device which restricts the movement range of the mirror-upshock-absorbing lever 343 in the mirror-up state also includes themirror-down shock-absorbing lever 341, and since the device whichrestricts the movement range of the mirror-down shock-absorbing lever341 in the mirror-down state also includes the mirror-up shock-absorbinglever 343, there is no need to provide a separate member for restrictingthe movement ranges of the mirror-down shock-absorbing lever 341 and themirror-up shock-absorbing lever 343, so that a superior shock-absorbingcapability can be achieved with a simple structure having a small numberof components.

In addition, when the movable mirror 15 is rotated to the mirror-upposition, the mirror-up shock-absorbing lever 343 that absorbs shock issupplementally pressed and moved by the mirror-down shock-absorbinglever 341 until the position corresponding to the mirror-up state (seeFIG. 49); and when the movable mirror 15 is rotated to the mirror-downposition, the mirror-down shock-absorbing lever 341 that absorbs shockis supplementally pressed and moved by the mirror-up shock-absorbinglever 343 until the position corresponding to the mirror-down state (seeFIG. 46). Accordingly, the mirror-down shock-absorbing lever 341 and themirror-up shock-absorbing lever 343 can be reliably and securely movedto a position after shock absorbing. According to this structure, evenif the biasing forces of the mirror-down shock-absorbing spring 342 andthe mirror-up shock-absorbing spring 344 are set at strong amounts,since the rotation of the movable mirror 15 to the mirror-down positionand to the mirror-up position is not hindered, the degree of freedom forsetting the shock-absorbing capability using the mirror-downshock-absorbing lever 341 and the mirror-up shock-absorbing lever 343 isimproved. Furthermore, due to the relationship of the supplementallypressing movements of the mirror-down shock-absorbing lever 341 and themirror-up shock-absorbing lever 343 that are mutually carried out oneach other, there is no need to provide a separate mechanism for suchsupplementally pressing movements so that the number of components doesnot increase.

Note that in the mirror shock absorbing mechanism 40F, the mirror-downshock-absorbing lever 341 and the mirror-up shock-absorbing lever 343are provided with the inclined cam surface 41 i and the inclined camsurface 43 k, respectively, and is configured so that the supplementalpressing movements of the mirror-down shock-absorbing lever 341 and themirror-up shock-absorbing lever 343 can be carried out during themirror-up operation and during the mirror-down operation, respectively,using the two inclined cam surfaces 41 i and 43 k. Alternatively, aconfiguration also possible in which only one of the inclined camsurfaces 41 i and 43 k is provided to assist only one of the movement ofthe mirror-up shock-absorbing lever 343 during the mirror-up operationand the movement of the mirror-down shock-absorbing lever 341 during themirror-down operation, respectively. Namely, the present invention isachieved if at least one of a first shock-absorbing member (mirror-downshock-absorbing lever 341) that absorbs shock during the mirror-downoperation and a second shock-absorbing member (mirror-up shock-absorbinglever 343) that absorbs shock during the mirror-up operationsupplementally presses and moves the other of the first and secondshock-absorbing members.

Although the present invention has been described with reference to theabove illustrated embodiments of the mirror shock absorbing mechanisms,the present invention is not limited to these particular embodiments.For instance, although the shock absorbing member (the mirror-downshock-absorbing lever 41, 141, 241 or 341) which absorbs bouncing of themovable mirror 15 when the movable mirror 15 rotates to the downposition is a rotational member which rotates about the shaft 41 x whilethe shock absorbing member (the mirror-up shock-absorbing lever 43, 143,245 or 343, or the release lever 243) which absorbs bouncing of themovable mirror 15 when the movable mirror 15 rotates to the up positionis a linearly moving member in each of the above described embodimentsof the mirror shock absorbing mechanisms, a combination of the mannersof movement (directions of movement) of these shock absorbing membersthat operate when the movable mirror 15 rotates to the mirror-upposition and when the movable mirror 15 rotates to the mirror-downposition can be made different from above.

Additionally, according to the present invention, the detailed shape ofeach shock absorbing member for the movable mirror 15 can be differentfrom that in each of the above described embodiments. For instance, eachof the third and fourth embodiments of the mirror shock absorbingmechanism 40C and 40D is provided on the mirror-down shock-absorbinglever 141 side with the downward movement restricting arm 41 e as aprojection that projects radially outwards to serve as a movementrestricting portion which limits the range of movement of the mirror-upshock-absorbing lever 143 in a state where the movable mirror 15 is inthe up position, and the downward movement restricting arm 41 e is madeto face the downward movement restricted projection 43 g of themirror-up shock-absorbing lever 143; however, it is possible for aprojection corresponding to the downward movement restricting arm 41 eto be formed on the mirror-up shock-absorbing lever 143 with noprojection formed on the mirror-down shock-absorbing lever 141.

Additionally, a torsion spring such as the mirror-down shock-absorbingspring 42, 142, 242 or 342 or the mirror-up shock-absorbing spring 46,146 or 246 and an extension spring such as the mirror-up shock-absorbingspring 44, 144 or 344 or the release spring 244 can be freely combinedto be used as each of the biasing members for biasing the aboveillustrated shock absorbing members; moreover, a biasing member otherthan such a torsion spring or an extension spring can also be used. Forinstance, it is possible to modify the fifth embodiment of the mirrorshock absorbing mechanism 40E so that the release lever 243 is biased bya torsion spring such as the mirror-up shock-absorbing spring 246 andthe mirror-up shock-absorbing slider 245 is biased by an extensionspring such as the release spring 244.

Obvious changes may be made in the specific embodiments of the presentinvention described herein, such modifications being within the spiritand scope of the invention claimed. It is indicated that all mattercontained herein is illustrative and does not limit the scope of thepresent invention.

What is claimed is:
 1. A movable mirror shock-absorbing mechanism of acamera, comprising: a movable mirror which is supported to be rotatablebetween a viewfinder light-guiding position, in which said movablemirror is positioned in a photographing optical path to reflect incidentlight from an object toward a viewfinder optical system, and a retractedposition, in which said movable mirror is retracted from saidphotographing optical path to allow said object light to travel toward aphotographic light-receiving medium; a mirror-retracting shock-absorbingmember which comes into contact with, and is pressed and moved in afirst pressing-moving direction by, said movable mirror to absorb shockof said movable mirror when said movable mirror rotates from saidviewfinder light-guiding position to said retracted position; and amirror-advancing shock-absorbing member which is held in a limitposition in which a range of movement of said mirror-retractingshock-absorbing member in a direction opposite to said firstpressing-moving direction is limited when said movable mirror is in saidretracted position, wherein said mirror-advancing shock-absorbing membercomes into contact with, and is pressed and moved in a secondpressing-moving direction by, said movable mirror from said limitposition to release the limitation of said range of movement of saidmirror-retracting shock-absorbing member and to absorb shock of saidmovable mirror when said movable mirror rotates from said retractedposition to said viewfinder light-guiding position.
 2. The movablemirror shock-absorbing mechanism according to claim 1, furthercomprising: a first biaser which biases said mirror-advancingshock-absorbing member in a direction opposite to said secondpressing-moving direction; and a second biaser which biases saidmirror-retracting shock-absorbing member in a direction opposite to saidfirst pressing-moving direction, wherein said mirror-retractingshock-absorbing member is linearly movable along a plane substantiallyorthogonal to an axis of rotation of said movable mirror, wherein saidmirror-advancing shock-absorbing member is rotatable about a shaftsubstantially parallel to said axis of rotation of said movable mirror,and wherein said movable mirror shock-absorbing mechanism furthercomprises a rotational limit portion which limits rotational movement ofsaid mirror-advancing shock-absorbing member in said biasing directionof said first biaser to hold said mirror-advancing shock-absorbingmember in said limit position.
 3. The movable mirror shock-absorbingmechanism according to claim 2, wherein said mirror-advancingshock-absorbing member comprises a movement restricting portion whichprojects outwardly in a radial direction of said shaft, wherein saidmovement restricting portion moves into a path of movement of arestricted portion formed on said mirror-retracting shock-absorbingmember to restrict movement of said mirror-retracting shock-absorbingmember in said biasing direction of said second biaser by engagement ofsaid movement restricting portion with said restricted portion when saidmirror-advancing shock-absorbing member is in said limit position, andwherein a rotation of said mirror-advancing shock-absorbing member fromsaid limit position in a direction opposite to said biasing direction ofsaid first biaser causes said movement restricting portion to retractfrom said path of movement of said restricted portion to release saidrestriction of said movement of said mirror-retracting shock-absorbingmember in said biasing direction of said second biaser.
 4. The movablemirror shock-absorbing mechanism according to claim 3, wherein saidmovement restricting portion of said mirror-advancing shock-absorbingmember comprises a slide contact surface which contacts said restrictedportion by said biasing force of said first biaser during movement ofsaid mirror-retracting shock-absorbing member when saidmirror-retracting shock-absorbing member comes into contact with and ispressed and moved by said movable mirror, and wherein saidmirror-retracting shock-absorbing member is pressed and moved by saidmovable mirror while said restricted portion is in sliding contact withsaid slide contact surface.
 5. The movable mirror shock-absorbingmechanism according to claim 2, wherein said camera comprises a mirrorbox which accommodates and supports said movable mirror between a pairof laterally-opposed side walls, wherein said mirror-retractingshock-absorbing member and said mirror-advancing shock-absorbing memberare supported by one of said pair of side walls of said mirror box, andwherein said rotational limit portion is formed on said one of said pairof side walls of said mirror box.
 6. The movable mirror shock-absorbingmechanism according to claim 2, wherein said camera comprises a mirrorbox which accommodates and supports said movable mirror, wherein saidfirst biaser comprises a torsion spring which is engaged with saidmirror box and said mirror-advancing shock-absorbing member, and whereinsaid second biaser comprises an extension spring which is engaged withsaid mirror box and said mirror-retracting shock-absorbing member. 7.The movable mirror shock-absorbing mechanism according to claim 2,wherein said camera comprises a mirror box which accommodates andsupports said movable mirror, wherein said first biaser comprises atorsion spring which is engaged with said mirror box and saidmirror-advancing shock-absorbing member, and wherein said second biasercomprises a torsion spring which is engaged with said mirror box andsaid mirror-retracting shock-absorbing member.
 8. A movable mirrorshock-absorbing mechanism of a camera, comprising: a movable mirrorwhich is supported to be movable between a viewfinder light-guidingposition, in which said movable mirror is positioned in a photographingoptical path to reflect incident light from an object toward aviewfinder optical system, and a retracted position, in which saidmovable mirror is retracted from said photographing optical path toallow said object light to travel toward a photographic light-receivingmedium; a first shock-absorbing member which comes into contact with,and is pressed and moved by, said movable mirror to absorb shock of saidmovable mirror when said movable mirror rotates in one direction betweensaid retracted position and said viewfinder light-guiding position; anda second shock-absorbing member which comes into contact with, and ispressed and moved by, said movable mirror to absorb shock of saidmovable mirror when said movable mirror rotates in the other directionbetween said viewfinder light-guiding position and said retractedposition, wherein, when one of said first shock-absorbing member andsaid second shock-absorbing member is pressed and moved in apressing-moving direction by said movable mirror, the other of saidfirst shock-absorbing member and said second shock-absorbing memberrestricts a range of movement of said one of said first shock-absorbingmember and said second shock-absorbing member in a direction opposite tosaid pressing-moving direction.
 9. The movable mirror shock-absorbingmechanism according to claim 8, wherein each of said firstshock-absorbing member and said second shock-absorbing member is biasedby a biasing force to move in a direction opposite to saidpressing-moving direction, and wherein, when one of said firstshock-absorbing member and said second shock-absorbing member is pressedand moved by said movable mirror, the other of said firstshock-absorbing member and said second shock-absorbing member is held,by said biasing force, in a limit position in which a range of movementof said one of said first shock-absorbing member and said secondshock-absorbing member is limited.